| Physics at the University of Virginia | ||||||
| Academics | People | Research | Announcements | Facilities | Administration | Classes |
| Monday, September 20, 1999 | Dr. Merrick DeWitt | |
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4:00 PM, Room 204 Note Special Time |
Wayne State University | |
| Physics Building | “The Effects of Nuclear and Electronic Structure on Intense Fields” |
| Monday, October 25, 1999 | Dr. Robert Compton [Host: Jan Harrison] | |
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4:00 PM, Room 204 Note Special Time |
University of Tennessee | |
| Physics Building | “Handedness in the Universe: Chirality in Chemisty” |
| Monday, November 1, 1999 | Dr. Chandra Raman [Host: Bob Jones] | |
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4:00 PM, Room 204 Note Special Time |
M.I.T. | |
| Physics Building | “Optical Tools for Bose-Einstein Condensates” |
| Monday, November 22, 1999 | Timothy Newman [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “New phenomena from solvable models of quantum dynamics ” |
| The rich behavior of the dynamics of quantum systems is still being uncovered, both through theoretical and experimental research. In this talk I will discuss some recent work on simple quantum dynamical models, where exact predictions are possible. Despite their simplicity, these models exhibit curious phenomena, including quantum revivals, quantum carpets, and "the sound of one hand clapping". I will also attempt to answer the contemporary question "why not just solve these models on the computer?" |
| Monday, November 22, 1999 | Professor George Ruff [Host: Olivier Pfister] | |
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2:00 PM, Room 313 Note Special Time |
Bates College | |
| Physics Building | “Diode Lasers for Atom Traps” |
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Tuesday, November 30, 1999 Note Special Day |
Prof. Alexander Sergienko [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
Boston University | |
| Physics Building | “Polarized Entangled Photons In Quantum Communications and Optical Metrology” |
| A pair of photons (two-photon state) generated in the nonlinear process of type-II spontaneous parametric down conversion (SPDC) is strongly entangled in energy, polarization, time, and space (momentum). Although these two-photon entangled states have primarily been used in fascinating tests of some of the counterintuitive foundations of the quantum theory, their quantum features are also a powerful generator of novel practical applications which either outperform their classical counterparts or do not have any classical analogues at all. We shall discuss a several experimental results in the area of quantum communications and optical measurement. |
| Monday, December 6, 1999 | Dr. Mikhail Lukin [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
ITAMP/Harvard University | |
| Physics Building | “Ultra-Slow Light” |
| Monday, December 13, 1999 | Cass Sackett [Host: T. Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “Decoherence of Quantum Superpositions Coupled to Engineered Reservoirs” |
| The theory of quantum mechanics applies to closed systems. In such ideal situations, a single atom can exist, for example, in a superposition of being in two different positions at the same time. Real systems, in contrast, always interact with their environment, with the consequence that macroscopic quantum superpositions like Schrodinger's cat are not observed. Moreover, macroscopic superpositions decay so quickly that the dynamics of decoherence can not even be observed. However, mesoscopic systems offer the possibility of observing the decoherence of such quantum superpositions states of the motion of a single trapped atoms. Decoherence is induced by coupling the atoms to engineered reservoirs, where the coupling an state of the environment are under the experimenter's control. We exhibit this with three experiments, finding that the decoherence scales exponentially with the square of the size of the superposition. |
| Monday, January 17, 2000 | Dr. Smair Bali [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
Duke University | |
| Physics Building | “The Quest for Quantum Degeneracy in an Optically Trapped Gas of Fermions” |
| A quantum degenerate sample of cold dilute fermions is expected to yield new exciting physics since Pauli's exclusion principle forbids congregation of fermions in the same quantum state. A fascinating possibility is the formation of Cooper pairs, analogous to the BCS phase transition responsible for superconductivity and for superfluidity in liquid He-3. Lithium-6, a stable and naturally abundant fermionic isotope, is an excellent candidate because it has large and attractive interatomic interactions, a necessary requirement for the superfluid transition. However, the lowest lying spin states of lithium-6 are not magnetically trappable. This precludes the use of a magnetic trap, the only kind of trap in which BEC has been achieved for bosonic atoms. The possibility of achieving quantum degeneracy, whether boson or fermion, in an optical trap has been a long sought goal and is of intense current interest. This is because, unlike their magnetic counterparts, optical traps can trap all spin states and offer the possibility of arbitrary control of interatomic interactions via external magnetic fields. However, owing to the presence of unexplained heating rates, optical traps have failed to be stable. We have identified some of the important heating mechanisms. By minimizing their effect we have constructed an ultrastable optical trap consisting of a focused far-detuned CO2 laser beam, in which we confine lithium-6 atoms with a life-time of 300 secs. This is nearly a two order of magnitude improvement in stability over all previous optical traps, rivalling that of magnetic traps. We simultaneously confine the two lowest lying spin states of lithium-6 thus enabling efficient evaporative cooling toward Fermi degeneracy and, possibly, the superfluid transition. Measurements of anomalously large elastic collision cross-sections and observation of evaporative cooling of lithium-6 will be presented. |
| Monday, January 24, 2000 | Tom Killian [Host: Tom Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “From Laser-cooled Atoms to an Ultra cold Neutral Plasma” |
| Monday, February 14, 2000 | Samir Bali [Host: Louis Bloomfield] | |
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2:00 PM, Room 203 Note Special Time |
Duke University | |
| Physics Building | “Quantum Noise in Simple Atomic Systems” |
| Counter-intuitive predictions of quantum mechanics are most readily explored in the field of optics, where table-top experiments suffice to make sensitive measurements. A single atom, radiating in free space, is the simplest and most fundamental quantum optical system. It is particularly attractive for study of multiple measurements on a quantum system because, quite unlike the situation for a classical radiator, the detection of a radiated photon directly affects the probability of a subsequent emission. Indeed, measurement of fluctuations in the radiated intensity provided the first experimental evidence for such counter-intuitive quantum effects as photon antibunching and sub-Poissonian light. However, quantum fluctuations in the optical phase of the radiated light remain relatively unexplored. Especially remarkable is the fact that "squeezing" in single-atom fluorescence, a phase-sensitive quantum effect first predicted in 1981, has long eluded direct observation despite receiving considerable attention. The reason is that measurement of phase-sensitive nonclassical effects in atomic fluorescence presents severe experimental challenges. In this talk I will describe how we recently overcame these challenges to make the first measurements of single-atom squeezing spectra in the phase-dependent fluorescence of atoms radiating in free space. Our experimental scheme permits a valid comparison of the observations with our predictions, thus yielding a new and simple physical picture of phase-dependent quantum noise in atomic fluorescence. Results of a direct measurement of the two-time field correlations will also be presented. Our measurements help elucidate the basic atomic processes underlying "squeezing". Our observations are especially important because the measurement accuracy in current state-of-the-art cold atom interferometers and frequency standards is limited by quantum noise. Controlling the phase-dependent quantum noise may enable measurement beyond quantum limits. |
| Monday, February 21, 2000 | Cass Sackett [Host: Louis Bloomfield] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “Entanglement of Four Particles” |
| Quantum mechanics allows for many-particle wave functions that cannot be factorized into a product of single-particle wave functions, even when the constituent particles are entirely distinct. Such entangled states explicitly demonstrate the nonlocal character of quantum theory, have been suggested for use in high-precision spectroscopy, and are a fundamental element of schemes for quantum communication, cryptography, and computation. In general, the more particles which can be entangled, the more clearly nonclassical effects are exhibited and the more useful the states are for quantum applications. In pursuit of these goals, we have demonstrated a recently proposed entanglement technique applicable to trapped ions. Coupling between the ions is provided by the Coulomb interaction through their collective motional degrees of freedom, but actual motional excitation is minimized. Entanglement is achieved using a single laser pulse, and the method can in principle be applied to any number of ions. We used this technique to generate entangled states of two, and for the first time, four particles. |
| Monday, February 21, 2000 | Robert Hirosky [Host: Brad Cox] | |
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3:00 PM, Room 204 Note Special Time |
University of Ilinois, Chicago | |
| Physics Building | “Tevatron QCD and Beyond” |
| The D-Zero Experiment studies the world's most energetic hadron collisions at the Fermilab Tevatron accelerator. The study of such collisions provides our deepest glimpse into the structure of matter. Particularly hard scattering of hadron constituents may be evidenced by the production of hadronic `jets' or plumes of particles. I review several analyses of jet production from the recent collider run at the Tevatron and survey various physics objectives for `Run II' and beyond. |
| Monday, February 28, 2000 | Carlo Dallapicolla [Host: Brad Cox] | |
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3:00 PM, Room 204 Note Special Time |
University of Maryland | |
| Physics Building | “Studying CP Violation at the SLAC B- Factory” |
| One of the least-well tested areas of particle physics today is that of CP violation. Although it has been observed in certain particle decays, its origin and magnitude is not well understood. CP violation in particle interactions is a crucial ingredient in the Big Bang model's description of the predominance of matter over antimatter in the universe. A new physics program at the "B-Factory" at the Stanford Linear Accelerator is underway and promises to resolve this important issue. |
| Monday, February 28, 2000 | Malcolm Boshier [Host: Bloomfield] | |
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4:00 PM, Room 204 Note Special Time |
Centre for Optical and Atomic Physics - University of Sussex | |
| Physics Building | “Optics With Cold Atoms and Bose Condensates” |
| Monday, March 6, 2000 | Ted Liu [Host: Brad Cox] | |
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3:00 PM, Room 204 Note Special Time |
Lawrence Berkeley Laboratory | |
| Physics Building | “CP Violation at BaBar -- current status and future prospects” |
| In this talk I first present a brief overview of mixing and CP violation in the charm and beauty sectors. Then, I will present a status report from the BaBar experiment at the Stanford Linear Accelerator Center which has been designed especially to measure time-dependent asymmetries in the B meson decays whose interpretation in the Standard Model is directly related to the parameters of the Cabibbo-Kobayashi-Maskawa mixing matrix. At the end, I will comment on the future prospects. |
| Monday, March 20, 2000 | Nickolas Solomey [Host: Brad Cox] | |
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3:00 PM, Room 204 Note Special Time |
Enrico Fermi Institute - University of Chicago | |
| Physics Building | “Neutrino, Elementary Particle and SuperSTAR” |
| Today there is much concern about the tiny neutral particle the neutrino. It has been in the lime-light in the popular press from science magazines to headlines in the New York Times. This is a great change from when the particle was first postulated to exist. Even its advocates doubted its existence at that point. However, now, the neutrino plays a pivotal role in many major discoveries in elementary particle physics, astrophysics and cosmology, and will continue to be important to study for decades to come. This colloquium will describe the neutrino, discuss its major role in advancing our understanding of elementary particle physics and conclude with the exciting new results we can expect from future experiments currently under construction. |
| Monday, March 27, 2000 | Erics Wells [Host: Robert Jones] | |
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4:00 PM, Room 204 Note Special Time |
Kansas State | |
| Physics Building | “Very Slow H+ + D(1s) “Half” Collisions.” |
| The dissociation of the HD+(1s sigma) molecular ion from the vibrational continuum produces a H+ + D(1s) “half” collision, typically with a with a kinetic energy release upon dissociation of less than 0.5 eV. The vibrational continuum is populated by single ionization of the neutral molecule, which predominantly leads to creation of HD+ molecular ions, but about 1% of the time reaches the vibrational continuum,resulting in a dissociation. Using this natural particle accelerator, we study the charge transfer and elastic scattering in the H+ + D(1s) system at collision energies ( 0 =< Ek =< 1100 meV) much lower than have previously been obtained. Our experimental results for both channels are compared to our coupled channels calculations. Additionally, the sum of the elastic and charge transfer channels relative to the HD+ channel is also compared to the expected ratio of bound-free to total transitions within the Franck-Condon approximation. |
| Monday, April 3, 2000 | Paul Padley [Host: Brad Cox] | |
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3:00 PM, Room 204 Note Special Time |
Rice University | |
| Physics Building | “Why Bother with Particle Physics?” |
| As physicists we should continually ask ourselves what we think the most compelling questions to be resolved are. In particle physics we have the "Standard Model" which explains all confirmed experimental results. So, should we even continue to pursue this line of research? This talk will show that there are very important questions that need to be addressed, that in fact the Standard Model is far from complete. Furthermore these questions must be addressed through experiment. I will argue that a program of Hadron Collider physics (in particular the LHC) has the best chance of moving us past the Standard Model. I will also show examples of the many technological challenges that we face in computing and engineering that make the practice of experimental particle physics truly interdisciplinary. |
| Monday, April 10, 2000 | Dr. David J. Wineland [Host: Thomas Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “Entanglement Experiments with Trapped Ions” |
| Monday, April 17, 2000 | James P. Shaffer [Host: Robert Jones] | |
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4:00 PM, Room 204 Note Special Time |
The National Research Council, The Steacie Institute for Molecular Sciences, Ottawa, ON, Canada | |
| Physics Building | “Probing Excited States of Ultracold Molecules Using Photoassociative Spectroscopy” |
| We describe the spectroscopy of highly excited states of ultracold molecules. We use a new photoassociative approach based on resonantly enhanced multiphoton ionization to probe these systems. We excite a large number of rotational states which provides a rich rovibrational spectrum. We are able to use this spectrum to extract not only the first order quadrupole-quadrupole and Van der Waals constants but also sensitive atom-atom interaction parameters such as the spin-spin, spin-orbit, and perturbative constants which arise from interactions between different zeroth order molecular states. This technique also allows information to be obtained about near dissociation collisions. The near dissociation regime is difficult to probe using other techniques. |
| Monday, April 24, 2000 | Michael Robinson | |
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4:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “Spontaneous Evolution of Rydberg Atoms to a Cold Plasma” |
| Monday, September 25, 2000 | Brett DePaola [Host: Bob Jones] | |
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4:00 PM, Room 204 Note Special Time |
Kansas State University | |
| Physics Building | “Collision physics with a laser-prepared target” |
| Monday, October 16, 2000 | Akira Terasaki [Host: Louis Bloomfield] | |
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4:00 PM, Room 204 Note Special Time |
Cluster Research Laboratory, Toyota Technological Institute | |
| Physics Building | “Electronic Structures and reactions of transition-metal-cluster ions” |
| From recent extensive studies on atomic and molecular clusters, it has been shown that their physical and chemical properties alter dramatically as a function of the number of constituent atoms (cluster size). Particularly, clusters of transition-metal elements attract attention because they are expected to possess novel characters in magnetism and catalysis. Since these properties originate from the electronic and geometric structures, it is essentially important to investigate their structures by both experimental and theoretical studies. From the experimental side, the laser spectroscopy of size-selected cluster ions is one of the most powerful means for this purpose. From the theoretical side, on the other hand, recent advances in density-functional theory (DFT) provide powerful tools to search for the optimized geometry and to calculate the electronic structures of small clusters. The theoretical approach to the analysis of the experimental results allows understanding of the size-specific properties of those clusters. On the basis of this strategy we have carried out photoabsorption and photoelectron spectroscopies of small cluster ions of cobalt, vanadium and manganese. Discussion is made by focusing on their magnetic properties. Regarding reactivity, our recent experiments on the reaction of nickel cluster ions with a methanol molecule have revealed reaction processes clearly dependent on the cluster size. |
| Monday, November 13, 2000 | Andy Dally & Hontao Zhang | |
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4:00 PM, Room 204 Note Special Time |
UVA | |
| Physics Building | “Photoelectron Spectroscopy of Alkali-Halide by Andy Dally and Magnetic Properties of Clusters by Hongtao Zhang ” |
| Monday, November 27, 2000 | Laburthe Bruno [Host: Tom Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
Laboratoire Aime Cotton, CNRS Orsay France | |
| Physics Building | “Formation of ultra cold cesium molecules through photoassociation” |
| Monday, December 11, 2000 | Frederick Fatemi [Host: Thomas Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “Atoms See the Light: Making Molecules From Ultracold Atoms” |
| Photoassociation, the process by which two free atoms absorb a photon to form a bound, excited molecule, is an extremely powerful tool for studying long-range atom-atom interactions. In a sample of trapped, ultracold (T < 1 mK) atoms, the technique is most often used to obtain high resolution spectroscopy of electronically-excited molecules near their dissociation limit. However, we have recently used this technique to monitor and manipulate collisions of ultracold atoms, and to produce weakly bound, translationally cold molecules in their electronic ground state. I will discuss some of these recent interesting results from the Laser Cooling and Trapping Group at NIST. |
| Monday, February 12, 2001 | Jason Ziebel [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “Probing the Momentum Distribution of Continuum Wavepackets Using Electron - Ion Recombination” |
| We have used ultrashort, nearly unipolar "half cycle" electric field pulses (HCPs) as a tool to measure the time-dependent momentum distribution of electrons in a Stark induced continuum. Ca atoms in an external field are excited from the ground state into an intermediate 4s4p state with a nanosecond dye laser. A 1 ps laser pulse with a bandwidth of approximately 20cm-1 promotes the 4s4p atoms to the field induced continuum, with an energy just above the saddle point in the Stark potential. At a variable time delay Delta-t following the excitation of the continuum wavepacket, the system is exposed to a HCP which imparts a non-zero linear momentum "kick". The portion of the probability distribution moving antiparallel to the applied kick suffers a reduction in its total energy. The fraction of probability amplitude whose energy is below the saddle-point forms a bound wavepacket. Because the recombination probability depends on the kick strength and distribution of momentum along the kick direction, the time-dependent momentum distribution of the continuum wavepacket can be recovered from measurements of recombination probabilities versus kick strength, orientation of the momentum kick, and time delay Delta-t. |
| Monday, February 19, 2001 | Min Xiao [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
Univ. of Arkansas | |
| Physics Building | “Atomic Coherence in Multi-Level Atomic Systems and Its Applications” |
| Atomic coherence effects in multi-level atomic systems, such as electromagnetically induced transparency and enhanced dispersion with reduced absorption, will be presented. I will discuss some interesting applications of such atomic coherence effects in nonlinear optical processes and group velocity reduction in such media. |
| Monday, March 19, 2001 | Santosh Pisharody [Host: O. Pfister] | |
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4:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “Stair-Step Decay of Autoionizing Wavepackets” |
| Monday, April 16, 2001 | Cherice Evans [Host: Thomas Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
Louisiana State University | |
| Physics Building | “Subthreshold photoionization in molecular dopant/perturber systems” |
| Monday, April 30, 2001 | Allen Landers [Host: Bob Jones/Eric Wells] | |
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4:00 PM, Room 204 Note Special Time |
Western Michigan | |
| Physics Building | “Photoelectron Diffraction Mapping: Molecules Illuminated from Within” |
| Much of our knowledge of the internal structure of matter results from the scattering and diffraction of electrons or X-rays. In many cases, the matter under investigation is in crystalline (or absorbate) form and can therefore be easily oriented in the laboratory. However, there are fundamental questions that may only be addressed through the direct study of single atoms or molecules (i.e. gas phase). It is therefore important that we seek methods which allow the detailed exploration of the orientation dependence of otherwise randomly oriented systems. I will discuss the use of a multiparticle coincidence technique to image the diffraction of an electron wave whose source is a specific site in a free molecule, i.e. core-level photoelectrons are used to illuminate the molecule from within. By choosing photons (and therefore photoelectrons) of appropriate energy, we can cause the photoelectron to resonate as it emerges through the molecular potential. This results in a richly structured electron diffraction pattern in the body-fixed frame of the randomly oriented molecule in the gas phase, and ultimately provides a unique "fingerprint" of the molecular potential. |
| Monday, July 9, 2001 | Frank Laloe [Host: Peter Arnold] | |
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4:00 PM, Room 204 Note Special Time |
Ecole Normale Superieure | |
| Physics Building | “Effect of the interactions in the Bose Einstein condensation of gases” |
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Wednesday, July 11, 2001 Note Special Day |
Itzik Ben-Itzhak [Host: Robert Jones] | |
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4:00 PM, Room 204 Note Special Time |
J. R. Macdonald Laboratory, Kansas State University | |
| Physics Building | “Imaging Dissociating Metastable He2+2” |
| Monday, October 15, 2001 | Robert Levis [Host: Robert Jones] | |
| 3:30 PM, Room 313 | Wayne State Univ. | |
| Physics Building | “Strong-Field Chemistry: Teaching Lasers to Selectively Break and Make Bonds” |
| Monday, November 12, 2001 | Brian King [Host: Cass Sackett] | |
| 3:30 PM, Room 313 | NIST | |
| Physics Building | “BEC...With a View Towards Neutral - Atom Quantum Information Processing” |
| Monday, March 18, 2002 | Wenhui Li [Host: L. Bloomfield] | |
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4:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “Microwave Spectroscopy of Cold Rydberg Atoms” |
| Monday, May 13, 2002 | Doug Chrisey [Host: Ian Harrison] | |
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4:00 PM, Room 313 Note Special Time |
US Naval Research Laboratory, Washington, D. C. | |
| Physics Building | “Laser Processing of Films: From High Tc Superconducting Films to Engineered Tissue Constructs” |
| Monday, October 7, 2002 | Francois Bondu [Host: Olivier Pfister] | |
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4:00 PM, Room 204 Note Special Time |
CNRS-Observatoire De La Cote Dazur | |
| Physics Building | “Interferometric detection of gravitational waves: technical issues and Challenges” |
| The detection of gravitational waves, predicted by general relativity, requires to detect the relative motion between masses at rest. An interferometric setup such as the one selected by VIRGO (project between France and Italy) or LIGO (US observatory) should have the required sensitivity to see severe astrophysical events. This requires to be able to control seismic noise, the thermal noise of the masses, the frequency noise of the laser, the shot noise on the photodiode detector, and to have high specifications on the mirrors (roughness, losses). Advanced interferometers will call for even advanced technologies: squeezed light, cryogenic mirrors, all reflective optical setups, advanced seismic isolations... |
| Monday, October 21, 2002 | Mike Chapman [Host: Cass Sackett] | |
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4:00 PM, Room 204 Note Special Time |
Georgia Tech | |
| Physics Building | “TBA” |
| Monday, April 7, 2003 | Bruno Laburthe-Tolra [Host: Thomas Gallagher] | |
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4:00 PM, Room 204 Note Special Time |
NIST | |
| Physics Building | “A Bose-Einstein condensate in optical lattices: study of a quantum gas in reduced dimensionalities” |
| Monday, April 14, 2003 | Albert Stolow [Host: Bob Jones] | |
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2:30 PM, Room 210 Note Special Time |
NRC Canada | |
| Physics Building | “Molecules in Non-Perturbative Laser Fields: Dynamics and Control” |
| Monday, April 21, 2003 | Olivier Pfister [Host: Robert Jones] | |
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4:00 PM, Room 204 Note Special Time |
UVA | |
| Physics Building | “Introduction to Nonclassical Light” |
| Monday, April 28, 2003 | Sheng Feng [Host: Bob Jones] | |
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4:00 PM, Room 204 Note Special Time |
UVA | |
| Physics Building | “Generation of Nonclassical Light States with An Ultrastable Optical Parametric Oscillator” |
| Monday, September 1, 2003 | Cass Sackett [Host: Cass Sackett] | |
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4:00 PM, Room 204 Note Special Time |
UVA - Department of Physics | |
| Physics Building | “Things You Should Pay Attention To As A Graduate Student in AMO Physics” |
| Monday, September 8, 2003 | Cass Sackett and Jessica Reeves [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Sackett: Saturated Absorption Spectroscopy and Laser Frequency Locks and Jessica Reeves: Stable Operation of a Dichroic Atomic Vapor Laser Lock” |
| Monday, September 15, 2003 | Louis Bloomfield and Forrest Payne [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA - Department of Physics | |
| Physics Building | “ Bloomfield - A Brief Introduction to Magnetism in Clusters of Atoms. Payne - Considerations in the Development of an Atomic Cluster Source” |
| Monday, September 29, 2003 | Thomas Gallagher and Wenhui Li [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Resonant Energy Transfer Among Rydberg Atoms” |
| Monday, October 6, 2003 | Olivier Pfister and Sheng Feng [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Quantum Interference of Ultrastable Twin Beams” |
| Monday, October 13, 2003 | Uli Eichman [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | Max Born Institute in Berlin | |
| Physics Building | “Excitation routes and ionization dynamics of two-electron atoms in laser fields” |
| Monday, November 3, 2003 | Bob Jones [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Multi-Photon Processes” |
| Monday, November 10, 2003 | Bob Jones [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Multi-Photon Processes” |
| Monday, November 24, 2003 | Thomas Gallagher/Haruka Maeda [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Non dispersing Wave packets” |
| Monday, December 1, 2003 | Olivier Pfister/Raphael Pooser [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Heisenberg-limited interferometry with twin boson modes: not such a bad idea after all...” |
| In this talk, we'll introduce the fundamental limits to interferometric (and spectroscopic) measurements and discuss the particular technique of Bayesian twin-mode interferometry, introduced by Holland and Burnett [1,2]. We will present new results of numerical simulations that show that, contrary to what had been predicted thereafter [3], experimental feasibility is quite promising, indeed.
[1] M.J. Holland and K. Burnett, Phys. Rev. Lett. 71, 1355 (1993). [2] T. Kim, O. Pfister, M.J. Holland, J. Noh, and J.L. Hall, Phys. Rev. A 57, 4004 (1998). [3] T. Kim, Y. Ha, J. Shin, H. Kim, G. Park, K. Kim, T.-G. Noh, C.K. Hong, Phys. Rev. A 60, 708 (1999). |
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Thursday, January 22, 2004 Note Special Day |
Enam Chowdhury [Host: Bob Jones] | |
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4:00 PM, Room 204 Note Special Time |
University of Delaware | |
| Physics Building | “Ultra-Intense Field Physics:Atomic Response” |
| There is a paradigm shift from high fields (below ~1016 W/cm2) to ultra-high fields, in terms of basic atomic response to the light field. Electron motion becomes relativistic, dipole approximation breaks down, magnetic fields of the light play an important role. What happens to an atom/ion in such an intense field? How are electron correlation effects (e.g. 2 electron wave-packet dynamics) modified? I will try to shed light on some of these topics. Also, I will discuss some novel techniques that we have developed to facilitate the achievements of such fields in table top experiments. |
| Monday, February 2, 2004 | Bob Jones [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Electronic Wavepackets” |
| Monday, February 9, 2004 | Professor Theodor Hansch [Host: Department of Physics] | |
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7:00 PM, Room 203 Note Special Time |
Director of Max Panck Institute | |
| Physics Building | “Ultra-Precise Laser Spectroscopy: Counting the Ripples of a Light Wave” |
| Monday, February 9, 2004 | Kevin Mitchell [Host: Bob Jones] | |
| 3:30 PM, Room 204 | College of William & Mary | |
| Physics Building | “Chaos induced pulse trains in the Ionization of Hydrogen” |
| Monday, February 16, 2004 | Olivier Pfister [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Ultrastable lasers and optical parametric oscillators” |
| Monday, March 15, 2004 | Cass Sackett [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Bloch Sphere” |
| Monday, March 22, 2004 | Olivier Pfister [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Second-quantized Bloch Sphere: The Schwinger Representation” |
| Monday, March 29, 2004 | Cass Sackett [Host: Paul Fishbane] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Atom Interferometry & Pulse Diffusion” |
| Monday, April 5, 2004 | Richard Barnes [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Quantum error Correction With continuous Variables” |
| Monday, April 19, 2004 | Jessica Reeves [Host: Olivia Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “BEC: Production: How To make A Condensated” |
| Monday, April 26, 2004 | Ofir Garcia [Host: Paul Fishbane] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “A New Type Of Interferometer Using BEC” |
|
Tuesday, May 18, 2004 Note Special Day |
Wei Yang [Host: Thomas Gallagher] | |
|
2:00 PM, Room 204 Note Special Time |
College of William & Mary | |
| Physics Building | “Characterization of the transient behaviour in a colliding pulse mode locked laser” |
|
Thursday, August 5, 2004 Note Special Day |
Goran Pichler [Host: Tom Gallagher] | |
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4:00 PM, Room 313 Note Special Time |
Institute of Physics, University of Zagreb | |
| Physics Building | “New Aspects in Detention and Formation of Ultracold Molecules” |
| Monday, September 13, 2004 | Cass Sackett | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “The Two - Level Atom” |
| Monday, September 27, 2004 | Haruka Maeda [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Classical Manipulation of Rydberg Atoms” |
| Monday, October 4, 2004 | Lou Bloomfield | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Feedback and Servos” |
| Monday, October 18, 2004 | Tom Gallagher | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Rydberg Wavepackets” |
| Monday, October 25, 2004 | Dan Pinkham | |
|
4:00 PM, Room 204 Note Special Time |
UVa | |
| Physics Building | “Transient Molecular Alignment” |
| Monday, October 25, 2004 | Bob Jones | |
| 3:30 PM, Room 204 | UVa | |
| Physics Building | “Molecular Dynamics in Intense Laser Fields” |
| Monday, November 8, 2004 | Forrest Payne [Host: Lou Bloomfield] | |
|
4:00 PM, Room 204 Note Special Time |
UVA | |
| Physics Building | “Magnetism in Clusters” |
| Monday, November 8, 2004 | Songbai Ye [Host: Lou Bloomfield] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Cluster Electronic Dynamics” |
| Monday, November 15, 2004 | Bret Sickmiller [Host: Bob Jones] | |
|
4:00 PM, Room 204 Note Special Time |
UVA | |
| Physics Building | “HHG in Hollow Core Waveguides: Phase-Matching and Molecular Alignment Effects” |
| Monday, November 15, 2004 | Bob Jones | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “High-Harmonic Generation in Gases” |
| Monday, November 22, 2004 | Jietai Jing [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Generation of Multipartite Entangled States and its Applications ” |
| Monday, November 29, 2004 | Olivier Pfister | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Multipartite Continuous-Variable Entanglement From Concurrent Nonlinearities” |
| Monday, December 6, 2004 | John Yukich [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | Davidson College | |
| Physics Building | “Photodetachment From Trapped Ions in External Fields” |
| What are negative ions, and why should we be interested in them? And what is photodetachment? In this talk I briefly present some of the pertinent background to negative ions and the field of photodetachment dynamics. I will then describe several experiments spanning the areas of continuum electron wavepackets, detachment in external electric and magnetic fields, and precision detachment spectroscopy. |
| Monday, January 17, 2005 | Vladimir Akulin [Host: Thomas Gallagher] | |
|
11:00 AM, Room 204 Note Special Time |
Laboratoire Aime Cotton - Orsay, France | |
| Physics Building | “Non-holonomic Control and Coherence Protection by the Zeno Effect ” |
| Monday, January 24, 2005 | Kareljan Schoutens [Host: Paul Fendley] | |
| 3:30 PM, Room 204 | University of Amsterdam | |
| Physics Building | “Phases of Rotating Bosons” |
| We discuss states of matter that arise when ultra-cold, Bose-condensed atoms are made to rotate. For not-too-high rotation, triangular vortex lattices have been observed. We discuss the nature of similar lattices for the case of bosons with 2 or 3 degenerate components. We also discuss the atomic quantum Hall states that are expected to form after a quantum melting of the vortex lattice at ultra-high rotation, and present experimental signaturesof such states. |
| Monday, January 31, 2005 | AVAILABLE | |
| 3:30 PM, Room 204 | ||
| Physics Building | “TBA” |
| Monday, February 7, 2005 | Raphael Pooser [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Multipartite Continuous Variable Entanglement Using Concurrent Nonlinearities” |
|
Sunday, February 13, 2005 Note Special Day |
AVAILABLE | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 14, 2005 | Iddo Ussishkin [Host: Paul Fendley] | |
| 3:30 PM, Room 204 | Minnesota | |
| Physics Building | “The Nernst Effect in High-temperature Superconductors” |
| One of the puzzles of high-temperature superconductivity concerns the nature of the non-superconducting state above the critical temperature T_c. Recently, a measurement of the Nernst effect, a transverse thermoelectric response, revealed an anomalously large Nernst signal above T_c which is very different from that observed in conventional materials. In this talk, I discuss the theory of the Nernst effect in the cuprates. I will argue that at least in a part of the phase diagram, corresponding to the overdoped cuprates, the puzzle can be explained within the theory of superconducting fluctuations. For the underdoped case, I will consider the limitations set by the Nernst effect measurements on possible theoretical scenarios. |
| Monday, February 21, 2005 | AVAILABLE | |
| 3:30 PM, Room 204 | ||
| Physics Building | “TBA” |
| Monday, February 28, 2005 | Bob Jones | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Stark Effect” |
| Monday, March 14, 2005 | Olivier Pfister | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Ultra-high Resolution Molecular Spectroscopy: Hyperfine Interactions and Internal Symmetry Breakings” |
| Monday, March 21, 2005 | Robert Jones | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Stark Effect” |
| Monday, March 28, 2005 | Olivier Pfister | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Two-photon Raman Laser” |
| Monday, April 11, 2005 | Paul Tanner [Host: Tom Gallagher] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Dipole-dipole and van der Waals Interactions in Frozen Rydberg Gases” |
| Monday, April 18, 2005 | Jeremy Murray-Krezan [Host: Robert Jones] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “New Impulse Momentum Retrieval Techniques and Measurements” |
| Monday, April 25, 2005 | Daruo Xie [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Production of Non-classical Light of Squeezed State by OPA” |
|
Tuesday, April 26, 2005 Note Special Day |
Edgar Vrendenbregt [Host: Thomas Gallagher] | |
|
4:00 PM, Room 313 Note Special Time |
Eindhoven University of Technology - The Netherlands | |
| Physics Building | “A Cold Atom Electron Source” |
| Monday, May 2, 2005 | Mike Timmins | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Zel'dovich Effect and Evolution of Atomic Rydberg Spectra Along the Periodic Table” |
| In 1959 Ya. B. Zel'dovich predicted that the bound-state spectrum of the non-relativistic Coulomb problem distorted at small distances by a short-range potential undergoes a peculiar reconstruction whenever this potential alone supports a low-energy scattering resonance. However documented experimental evidence of this effect has been lacking. Previous theoretical studies of this phenomenon were confined to the regime where the range of the short-ranged potential is much smaller than Bohr's radius of the Coulomb field. We go beyond this limitation by restricting ourselves to highly-excited s states. This allows us to demonstrate that along the Periodic Table of elements the Zel'dovich effect manifests itself as systematic periodic variations of the Rydberg spectra with a period proportional to the cubic root of the atomic number. This dependence, which is supported by analysis of experimental and numerical data, has its origin in the binding properties of the ionic core of the atom. |
| Monday, August 1, 2005 | Mark Hillery [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | Hunter College at the City University of New York | |
| Physics Building | “Entanglement Conditions for Two and Three Mode States” |
| This will be a chalkboard talk based on very recent work of the author and Suhail Zubairy from Texas A&M (see http://arxiv.org/abs/quant-ph/0507168 for more details) about finding new ways of detecting entanglement, with connections to experimental physics. |
| Monday, August 29, 2005 | AVAILABLE | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 5, 2005 | Cass Sackett | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Introduction and Atomic Units” |
| Monday, September 19, 2005 | Jessica Reeves | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Bose-Einstein Condensation and Atom Interferometry” |
|
Thursday, September 29, 2005 Note Special Day |
Thomas Pattard [Host: Thomas Gallagher] | |
|
4:00 PM, Room 313 Note Special Time |
Dresden | |
| Physics Building | “Ultracold Neutral Plasmas” |
| Recent advances in trapping and cooling of neutral atomic gases have permitted achieving ultralow temperatures far below 1K. With this, a wealth of new research fields has opened up, not at all limited to the realization of Bose Einstein condensation and related questions. In this talk, I will introduce one of these research topics, namely the physics of ultracold neutral plasmas. The fact that the plasma is many orders of magnitude colder than "conventional" plasmas leads to some remarkable properties, akin to conditions realized in exotic astrophysical environments. A theoretical description of these systems relies on methods and concepts bridging the gap between traditional atomic physics, plasma physics and nonequilibrium thermodynamics. On the other hand, this also means that the study of cold plasmas can provide new stimulus for all of these fields. |
| Monday, October 3, 2005 | *****READING DAY***** | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, October 10, 2005 | Russell Minns [Host: Bob Jones] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Battling Decoherence in Rydberg Quantum Bits” |
| Monday, October 31, 2005 | Olivier Pfister [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Continuous Variables in Qubits and Qudits: What's the Difference?” |
| Monday, November 21, 2005 | ****THANKSGIVING BREAK**** | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 28, 2005 | Olivier Pfister [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “The Schwinger Representation (or second-quantized Bloch sphere) and Quantum Interferometry” |
| Monday, December 5, 2005 | Ed Shuman [Host: Thomas Gallagher] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Revisiting the Core Polarization Model” |
| Monday, February 27, 2006 | RESERVED [Host: JKG] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “TBA” |
| Monday, March 6, 2006 | ****SPRING RECESS**** | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 20, 2006 | Wei Jiang [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Metal Cluster Magnetism” |
| Monday, March 27, 2006 | "RESERVED" [Host: JKG/SACKETT] | |
| 3:30 PM, Room 204 | "RESERVED" | |
| Physics Building | “"RESERVED"” |
| Monday, April 3, 2006 | Xiaodong Zhang [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Microwave Ionization of Sodium at High Scaled Frequency” |
| Monday, April 10, 2006 | Ben Deissler [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Atom Interferometry with Bose-Einstein Condensates” |
| Monday, April 17, 2006 | Xiangdong Zhang [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | UVA | |
| Physics Building | “Probing Time-Dependent Electron Interaction in Doubly-Excited Electron Wave Packets” |
| Monday, April 24, 2006 | Eun Oh [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | Naval Research Laboratory | |
| Physics Building | “NRL's Effort on Magnetic Guiding and Manipulation Using Atom-Chip and Permanent Magnets” |
| Monday, September 4, 2006 | Cass Sackett [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “An Introduction to AMO Physics” |
| Monday, September 11, 2006 | Cass Sackett [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “An Introduction to AMO Physics” |
| Monday, September 25, 2006 | Russell Minns [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Probing Dissociation Dynamics through a Conical Intersection in Ammonia” |
| Monday, October 9, 2006 | Reading Day [Host: N/A] | |
| 3:30 PM, Room 204 | N/A | |
| Physics Building | “N/A” |
| Monday, October 30, 2006 | Amber Post [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “An Overview of Atomic Clocks” |
| Monday, November 6, 2006 | Chandra Raman [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | The Georgia Institute of Technology (Georgia Tech) | |
| Physics Building | “Rings and Vortices in Matter Wave Experiments” |
| Quantum gases are rich systems that possess many parallels with condensed matter. Atomic physicists can avail themselves of many tools for shaping these gases and tailoring their properties. For example, one can create beautifully ordered lattices of quantized vortices within a Bose-Einstein condensate (BEC) by magnetic or optical "stirring" of the gas, similar to those observed in superconductors and liquid helium-3. In our laboratory at Georgia Tech we have used Bragg scattering to probe the momentum distribution of arrays of these vortices. In addition, I will also discuss our efforts to use optical forces to tailor the matter wave expansion of a BEC, with applications to atom optical focusing and guiding. |
| Monday, November 13, 2006 | John McCune | |
| 3:30 PM, Room 204 | SNL Financial | |
| Physics Building | “Alternative Careers for Physicists” |
| Monday, November 20, 2006 | Thanksgiving Recess [Host: N/A] | |
| 3:30 PM, Room 204 | N/A | |
| Physics Building | “N/A” |
|
Thursday, December 14, 2006 Note Special Day |
Nicolas Menicucci [Host: Olivier Pfister] | |
| 3:30 PM, Room 313 | Princeton University & University of Queensland | |
| Physics Building | “Universal Quantum Computation with Continuous-Variable Cluster States” |
| I will report on work published in PRL 97, 110501 (2006), in which my co-authors and I describe a generalization of the cluster-state model of quantum computation to continuous-variable systems, along with a proposal for an optical implementation using squeezed-light sources, linear optics, and homodyne detection. For universal quantum computation, a nonlinear element is required. This can be satisfied by adding to the toolbox any single-mode non-Gaussian measurement, while the initial cluster state itself remains Gaussian. Homodyne detection alone suffices to perform an arbitrary multi-mode Gaussian transformation via the cluster state. We also propose an experiment to demonstrate cluster-based error reduction when implementing Gaussian operations. |
| Monday, March 19, 2007 | Kurt Gibble [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | Penn State University | |
| Physics Building | “Physics with Atomic Clocks: Beyond What time is it?” |
| Atomic clocks realize the most accurate measurements of any kind and are extremely sensitive to incredibly small perturbations. The current generation of atomic clocks uses laser-cooling and, after circumventing some new problems, these will realize 100 fold improvements in clock accuracies. I will describe the basic physics of clocks, the motivations for building better clocks, and several of the new problems. The new problems include frequency shifts due to collisions of the cold atoms, the size of the recoil of an atom when it absorbs a photon, and juggling many atoms in fountains. Looking forward, the next generation of atomic clocks will utilize optical frequency transitions. I will describe this elegant technology that allows us to count at optical frequencies (1015 Hz). |
| Monday, March 26, 2007 | Chris Crawford [Host: Blaine Norum] | |
|
3:00 PM, Room 204 Note Special Time |
LANL | |
| Physics Building | “Parity Violation and the Neutron” |
| Parity violation, discovered in 1957 in nuclear beta decay, is unique to the weak interaction. This property makes it possible to isolate weak contributions from the residual strong force, which dominates hadronic interactions by 7 orders of magnitude. The NPDGamma experiment is being carried out at Los Alamos National Laboratory to extract the weak pion-nucleon coupling by measuring the parity violating asymmetry in radiative neutron-proton capture with polarized neutrons to an accuarcy of 5x10-9. I will describe this experiment and give some prelimary results. |
| Monday, April 2, 2007 | Mary Kutteruf [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Coherent Rydberg-Rydberg Collisions” |
| Monday, April 9, 2007 | Benjamin Lev [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | JILA | |
| Physics Building | “OH Stark deceleration: magnetic trapping, molecular qubits, and cavity-assisted laser cooling” |
| The experimental realization of large samples of ultracold, ground state polar molecules would be a major breakthrough for research in ultracold collisions and chemistry, quantum information processing, and the study of novel states of matter. To accomplish this goal, our research employs a Stark decelerator to slow a supersonic expansion of OH in its rovibronic ground state. At the decelerator's terminus, a 30 mK OH packet of density 10 4 cm -3 is caught and confined in a magnetic quadrupole trap. An adjustable electric field of sufficient magnitude to completely polarize the OH is superimposed on the trap in either a quadrupole or homogenous field geometry. The trap dynamics deviate from that governed by simple addition of the fields' forces on OH's magnetic and electric dipoles. Confinement of cold polar molecules in a magnetic trap, leaving large, adjustable electric fields for control, is an important step towards the study of low energy dipole-dipole collisions. The cold molecular packets produced via Stark deceleration have enabled us to perform precision microwave spectroscopy of the OH ground state structure, which serves as an important system for constraining variation of fundamental constants and for molecular quantum information processing. Future experiments will require much colder molecules, and we will briefly discuss prospects for cavity-assisted laser cooling of OH. |
| Monday, April 16, 2007 | Russell Bloomer [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Time-Modulated Bright Beam Squeezing and Non-Gaussian States of Light” |
| Optical Parametric Oscillators are an excellent source of squeezed light. These squeezed states have a positive Wigner function and are Gaussian. For these states, there exist a limit to which the total squeezing spectrum can be reduced. We attempt to experimentally demonstrate the creation of squeezed states that exceed this limit of noise reduction by modulating the pump beam. These new squeezed will have a negative Wigner function and will be non-Gaussian. I will outline future experimental uses of this non-Gaussian light. |
| Monday, April 30, 2007 | Jianing Han [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Superradiance in cold Rydberg atoms” |
| Monday, May 7, 2007 | Jonathan Habif [Host: Olivier Pfister] | |
| 3:30 PM, Room 205 | BBN Technologies | |
| Physics Building | “The DARPA Quantum Network: Scaling beyond one photon in Boston” |
| The DARPA Quantum Network has entered its final phase of development under the Quantum Information Science and Technology (QuIST) program. The most recent successful demonstrations have included the integration of state-of-the-art photon detectors, development of custom high-speed electronics, and experimental production of entangled states of light. I will discuss the details of the most recent milestones in the quantum network, and describe the path forward for growing the network. Furthermore, I will discuss how quantum coherent technology developed under the QuIST program can be leveraged in other technological arenas. |
| Monday, September 3, 2007 | Nicolas Menicucci [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | Princeton U. / U. of Queensland | |
| Physics Building | “The Bloch Representation of Quantum States with D > 2” |
| Quantum states are hard to visualize. This is true regardless of the system's dimension. Two cases are particularly nice, though: infinite-dimensional systems, for which quantum optics gives us the Wigner, P, and Q representations, and qubits, for which we can use the Bloch-vector representation. The Bloch picture can be generalized to states with finite dimension greater than two, but there are striking and important differences between the D = 2 and D > 2 Bloch pictures. This talk will introduce the Bloch representation of quantum states with D > 2 and will emphasize the similarities and differences as compared to the standard (qubit) case. |
| Monday, September 10, 2007 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 17, 2007 | Cass Sackett [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “An Introduction to Atomic Physics” |
| Monday, September 24, 2007 | Ben Deissler [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Measurement of ac Stark Shift with a Guided Wave Interferometer” |
|
Tuesday, September 25, 2007 Note Special Day |
Ashton Bradley [Host: Olivier Pfister] | |
|
5:00 PM, Room 204 Note Special Time |
Queensland | |
| Physics Building | “Theory and applications of the truncated Wigner method for ultra-cold Bose gases” |
| Following the great success of mean field theory in describing trapped Bose-Einstein condensates, there has recently been much interest in also including thermal and spontaneous processes which are not present in the mean field description. One way to do this involves using phase space methods which were developed in quantum optics to similarly extend the mean field theory of lasers. This talk will present an overview of theory and applications of the truncated Wigner method to ultra-cold Bose gas physics. We will cover the formal basis for the method, its connections to classical field methods and exact phase space methods, and discuss recent applications to a number of systems of experimental interest. |
| Monday, October 1, 2007 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, October 15, 2007 | Thibault Vogt [Host: Bob Jones] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Towards Transient Laser Orientation of Diatomic Molecules” |
| During the past ten years considerable attention has been devoted to the use of intense subpicosecond optical pulses to align and orient molecules (diabatic alignment and orientation). An intense pulse can give a momentum kick to the molecule, allowing for the creation of a rotational wavepacket and leading to periodic alignment and/or orientation. Although diabatic alignment was demonstrated several years ago, the ability to orient molecules using electric field pulses has yet to be proven experimentally. One possibility is to use an intense half-cycle pulse (terahertz radiation) which couples to the permanent dipole moment of a polar molecule (our case HBr). Another possibility is to overlap two electric laser field pulses with different optical frequencies (namely omega and 2*omega). In this seminar I will describe in more detail the different techniques for aligning and orienting molecules (static fields, laser fields) along with numerous possible applications in molecular and optical physics. I will also give an update on our recent computational and experimental efforts to achieve diabatic, field-free, orientation in the laboratory. |
| Monday, October 22, 2007 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, October 29, 2007 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 5, 2007 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 12, 2007 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 26, 2007 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, December 3, 2007 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, December 17, 2007 | Edward Grant [Host: Tom Gallagher] | |
| 3:30 PM, Room 204 | University of British Columbia | |
| Physics Building | “Spectroscopic Manifestations of High-Rydberg Dynamics (Intra- and Intermolecular)” |
| Monday, January 21, 2008 | Joseph R. Manson [Host: Vittorio Celli] | |
| 3:30 PM, Room 204 | Clemson University | |
| Physics Building | “Scattering of Small Molecules by Surfaces” |
| Scattering molecules from surfaces is one method of obtaining information about specific aspects of the molecule-surface interaction potential and about the exchange of energy between the various molecular degrees of freedom and the modes of surface excitation. Scattering experiments can also probe surface trapping and sticking and the initial precursors to chemical reactions. Many such experiments have been carried out using molecules with masses significantly heavier than hydrogen for which the translational and rotational degrees of freedom during the collision process can be approximated by classical mechanics. Described in this talk is a mixed classical-quantum theory of molecule-surface scattering that treats the translational and rotational motion of the molecule and the multiphonon excitation of the surface with classical mechanics while the internal molecular vibrational degrees of freedom are treated with quantum mechanics. Comparisons of calculations with recent experiments show that such a theory can be useful in explaining observed scattered angular distributions, translational energy-resolved spectra, energy transfer to molecular rotational modes, and excitation probabilities for internal vibrational modes. |
| Monday, January 28, 2008 | Jay Lowell [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | DARPA | |
| Physics Building | “An A to Z of Applied Physics Programs at DARPA” |
| Monday, February 4, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 11, 2008 | Reserved | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 18, 2008 | Qudsia Quraishi [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | Univ. of Colorado and NIST, Boulder | |
| Physics Building | “Optical frequency combs for stable radiation in the microwave, terahertz ” |
| Optical frequency combs (OFC) have dramatically changed the paradigm for precision optical frequency measurements. Modern precision measurements rely upon the comb to act as a frequency gear-work to bridge a reference frequency (microwave or optical) to another frequency of interest, which can result in 17 digits of measurement accuracy. For such frequency comparisons, which often span hundreds of nanometers, the noise contribution of the comb itself must be well understood. Additionally, beyond precision optical measurements, recent work has shown that very low phase noise microwave signals may also be extracted from OFCs. The limits to the combs' performance in the optical and microwave domains is a matter of current inquiry. In my talk, I will discuss noise properties associated with signals extracted from OFCs. In the case of the combs' optical signals, I will discuss the scaling of phase noise of OFCs across 240 nanometers of the combs' optical bandwidth. In the case of the combs microwave signals, I will discuss efforts currently underway to achieve very low phase noise signals, in the x-band range of 10 GHz, which exceed the performance of state-of-the-art microwave sources. Finally, I will discuss the integration of the comb with the terahertz domain to generate broadly tunable and narrow linewidth radiation in the terahertz regime. |
| Monday, February 25, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 10, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
|
Sunday, March 16, 2008 Note Special Day |
Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 17, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 24, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, April 7, 2008 | Matt Pysher [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Continuous-Variable Entanglement with Concurrent Nonlinearities” |
| Monday, April 14, 2008 | John Burke [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Phase Gradient Effects in a BEC Interferometer” |
| Monday, April 21, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, April 28, 2008 | Josh Gurian [Host: Cass Sackett] | |
|
3:00 PM, Room 204 Note Special Time |
University of Virginia | |
| Physics Building | “Multiphoton microwave ionization of Li Rydberg atoms” |
| Monday, May 5, 2008 | Seth Aubin [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | William and Mary | |
| Physics Building | “Ultra-cold quantum gases for many-body physics and interferometry” |
| I will present the design and construction of an apparatus for generating an ultra-cold Bose-Fermi mixture of 87Rb and 40K on an atom chip at the College of William and Mary. In the near term, the apparatus will support experiments on degenerate fermion interferometry. In the long term, we are directing our efforts towards producing an ultra-cold gas of polar KRb molecules for investigating novel types of bosonic and fermionic superfluidity |
|
Tuesday, May 20, 2008 Note Special Day |
Sasikumar Palaniyappan [Host: Bob Jones] | |
|
11:00 AM, Room 204 Note Special Time |
University of Delaware | |
| Physics Building | “Relativistic rescattering and multielectron ionization of atoms and molecules in strong and ultrastrong laser fields” |
|
Friday, July 11, 2008 Note Special Day |
Guglielmo Tino [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | LENS / Florence, Italy | |
| Physics Building | “Cold Atom Interferometry for Gravitational Experiments” |
|
Tuesday, August 5, 2008 Note Special Day |
Vladyslav Ivanov [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | LENS | |
| Physics Building | “Coherent manipulation of atomic wavefunctions in an optical lattice” |
| We present manipulations of a cloud of cold Sr 88 atoms in a vertical optical lattice potential. In particular we observe a resonant broadening of the atomic cloud by modulating the phase or the amplitude of the lattice potential. This broadening is caused by a resonant tunneling of an atomic wave functions between lattice cites. The width of the resonance spectra is determined only by the Fourier limit due to the absence of decoherence. This is experimentally confirmed up to 15 s of the modulation time. The small linewidth allows us to measure the local gravity with a sensitivity of 10 -6 g. We demonstrate stretching of an atomic wave function over a distance of 1 mm. Then atomic wave function can be refocused in controlled way, to a size close to initial. |
| Monday, August 25, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 1, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 8, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 15, 2008 | Cass Sackett [Host: Lou Bloomfield] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Introduction to AMO Physics” |
| Monday, September 22, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, September 29, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, October 6, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
|
Thursday, October 9, 2008 Note Special Day |
Klaus Muller-Dethlefs [Host: Tom Gallagher] | |
|
4:00 PM, Room 204 Note Special Time |
University of Manchester | |
| Physics Building | “ZEKE Rydberg states in a crowd and "Condensed Rydberg Clusters": A new state of matter?” |
| Monday, October 13, 2008 | Mudessar Shah [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | University of Michigan | |
| Physics Building | “Cold Rydberg atoms dynamics and ultracold plasmas in high magnetic ” |
| We investigate cold Rydberg and plasmas in a particle trap that has the unique capability to simultaneously laser-cool and trap neutral atoms as well as to confine plasmas in magnetic fields of about three Tesla. The atom trap is a high-field Ioffe-Pritchard laser trap, while the plasma trap is a Ioffe-Penning trap that traps electrons and ions in separate wells. The observed plasma dynamics is characterized by a breathing-mode oscillation of the positive (ionic) plasma component, this feeds back on the behavior of the negative (electron) component of the plasma. At higher densities, the observed oscillations become nonlinear. The electron component has been found to undergo rapid cooling. We further report on the recombination of magnetized plasmas into Rydberg atoms in transient traps and quasi-steady-state traps. In transient traps, large numbers of recombined Rydberg atoms in high-lying states are observed. In quasi-steady-state traps, the measured numbers of recombined atoms are lower and the binding energies higher. |
| Monday, October 20, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, October 27, 2008 | Richard Overstreet [Host: Tom Gallagher] | |
| 3:30 PM, Room 204 | University of Oklahoma | |
| Physics Building | “Interactions between Pairs of Cs Rydberg Atoms” |
| Monday, November 3, 2008 | Reserved [Host: Paul Fendley] | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 10, 2008 | Danielle Braje [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | NIST | |
| Physics Building | “Optical frequency combs with microwave repetition rates” |
| Femtosecond laser frequency combs have intrinsic properties which make them enticing tools for modern laser physics: a broad frequency spectrum of more than an octave of bandwidth; a temporally short pulse width of several femtoseconds; an evenly spaced array of narrow frequency modes; and the ability to stabilize both the spacing and absolute position of the comb frequencies. These combined attributes make femtosecond combs a near perfect frequency standard or in essence, an ideal ruler for optical frequencies. A limitation of current state-of-the-art comb technology, however, stems from the closely spaced tics of this optical-frequency ruler. With typical frequency-modes spaced from 100 MHz to 1 GHz, individual comb lines are not readily distinguished. For applications such as high resolution spectrograph calibration, direct laser- frequency-comb spectroscopy, low-noise microwave generation, astronomy and optical waveform synthesis / fabrication, larger frequency mode spacing is necessary. I will discuss how current fs lasers may be tailored to overcome these limitations as well as other avenues for generation of widely spaced combs. In particular, I will focus on a novel, self-seeded monolithic resonator comb, which directly generates a 10 GHz comb. Through cascaded four-wave mixing (hyper- parametric oscillation), a cw-pumped, highly nonlinear fiber resonator cavity produces a comb that is centered at 1550nm with tailorable, mode spacing in the gigahertz range and spanning ∼ THz. |
| Monday, November 17, 2008 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, November 24, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, December 1, 2008 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, January 12, 2009 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, January 19, 2009 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, January 26, 2009 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 2, 2009 | Reserved for HEP Seminar | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 9, 2009 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 16, 2009 | Available | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, February 23, 2009 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 9, 2009 | Reserved for Nuclear/Elementary Particle Seminar [Host: Dinko Pocanic] | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, March 16, 2009 | Alexey Tonyushkin [Host: Cass Sackett] | |
| 3:30 PM, Room 204 | Harvard | |
| Physics Building | “Guided Atom Interferometry with Thermal Atoms” |
| Recent growth of the atom interferometry field is being driven by the wide array of its possible applications in precision measurements of the fundamental physical constants, and for sensing of inertial effects. Inertial sensing such as rotation was one of the first and one of the most practically important demonstrated applications for atom interferometers. Many believe that cold atom-based interferometer for rotational sensing – a device called a gyroscope – can be both compact and highly sensitive. In my talk, I review various types of atom interferometers and show that cold thermal atoms are well suited for atom interferometry. I will also talk about our recent implementation of a quantum kicked rotor, a system whose classical counterpart exhibits chaos, in a guided atom interferometer. I will discuss the applications of our quantum kicked rotor to accurate measurements of gravitational acceleration and atomic recoil frequency as well as to study a quantum-classical correspondence principle. |
| Monday, March 23, 2009 | Piotr Deuar [Host: Cass Sackett] | |
|
4:00 PM, Room 313 Note Special Time |
LPTMS | |
| Physics Building | “The Superfluidity of Dipolar Fermi Gases” |
| With the recent advances in cooling of heteronuclear dipolar molecules to their rovibrational ground state, the prospect of ultra-cold gases of fermionic dipoles in the lab is becoming realistic. Accordingly, the low energy collective excitations have been calculated for a uniform single-species polarized gas of fermionic dipoles below the superfluid critical temperature in the dilute BCS regime. Its behaviour differs strongly from the standard s-wave BCS gas due to a node line in its quasiparticle excitation spectrum that resembles that in the hypothetical polar phase of He-3 and exotic superconductors. One finds: (1) Appreciable damping of collective modes occurs even at T=0 and far below the sound velocity. (2) An ``aligned superfluid'' regime with no analogue in the s-wave-interacting gas, occurs for temperatures greater than the excitation energy. Here good quality superfluidity occurs only in directions concentrated broadly around the polarisation, whereas other directions are strongly damped. Furthermore, in the "good" direction, this aligned superfluidity is much less damped than at T=0. |
| Monday, March 30, 2009 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
| Monday, April 6, 2009 | Reserved for CMP seminar | |
| 3:30 PM, Room 204 | ||
| Physics Building |
|
Wednesday, April 8, 2009 Note Special Day |
Claude Fabre [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | Universite Pierre et Marie Curie | |
| Physics Building | “Playing with quantum modes of light” |
| Multimode quantum systems have a high potential interest in many-qubit quantum computation, parallel quantum information processing and quantum metrology. We will show that some properties of multimode quantum states of light are 'intrinsic' , i.e. independent of the choice of the mode basis, and on the other hand that in many instances, it is very useful to identfiy particular modes that simplify the problem under consideration, such as the noise modes or the 'supermodes'. This will be illustrated by examples taken in the domains of 'quantum imaging' ( multi-transverse-mode quantum states) and 'quantum frequency combs' (multi-longitudinal-mode quantum states). |
| Monday, April 13, 2009 | Kelsie Betsch [Host: Lou Bloomfield] | |
| 3:30 PM, Room 204 | University of Virginia | |
| Physics Building | “Ultrashort Phase Locked Laser Pulses for Asymmetric Electric Field Studies of Molecular Dynamics” |
| Monday, April 20, 2009 | Sae Woo Nam [Host: Olivier Pfister] | |
|
4:00 PM, Room 313 Note Special Time |
NIST | |
| Physics Building | “Superconducting detectors for quantum information science and technology” |
| There is increasing interest in using superconducting optical photon detectors in a variety of applications in quantum information science and technology. These applications require detectors that have extremely low dark count rates, high count rates, and high quantum efficiency. I will describe our work on two types of superconducting detectors, the Single Photon Superconducting Detector (SSPD) and superconducting Transition-Edge Sensor (TES). An SSPD is an ultra-thin, ultra-narrow (nm scale) superconducting meander that is current biased just below its critical current density. When one or more photon is absorbed, a hot spot is formed that causes the superconductor to develop a resistance and consequently a voltage pulse. By exploiting the sharp superconducting-to-normal resistive transtion of tungsten at 100mK, TES detectors give an output signal that is proportional to the cumulative energy in an absorption event. This proportional pulse-height enables the determination of the energy absorbed by the TES and the direct conversion of sensor pulse-height into photon number. I will discuss our results of using both of these new types of detector in quantum information applications and our progress towards developing detectors with quantum efficiencies approaching 100%. |
| Monday, April 27, 2009 | RESERVED | |
| 3:30 PM, Room 204 | ||
| Physics Building |
|
Wednesday, April 29, 2009 Note Special Day |
Alexander Ling [Host: Olivier Pfister] | |
| 3:30 PM, Room 204 | NIST | |
| Physics Building | “Producing Photon-Pairs using non-linear optical waveguides” |
| Correlated photon-pairs are a useful resource in obtaining heralded single photons or for the generation of entangled pairs of qubits. The workhorse method of generating photon-pairs has been Spontaneous Parametric Down-Conversion inside bulk nonlinear optical crystals. However, the emission profile of such photon-pairs is always multi-mode, and the overall coupling efficiency into single-mode optical fibers is poor. In order to enhance the coupling efficiency, it is desirable to produce photon-pairs inside engineered waveguide structures that have a higher degree of overlap with single-mode fibers. In this talk, I will present some of our recent work in generating and characterizing photon-pairs using two types of waveguides: a) a waveguide formed from periodically-poled KTP, and b) a photonic-crystal fiber (PCF). With the waveguide source, we have demonstrated photon-pair production via two different SPDC phase-matching methods (Type-0 and Type-II) from a single waveguide, and at the same temperature. I will also present the measured coincidence spectrum for the two phase-matching methods and discuss the differences between them. The PCF source generates photon-pair via Four-Wave Mixing, and is a more mature source compared to the PPKTP waveguide. We have been able to demonstrate the generation of photon-pairs that are indistinguishable, as well as polarization-entangled. In this talk I will describe our recent innovations to improve the coupling efficiency and stability of this source. |
| Monday, May 11, 2009 | YAN-WEN TAN [Host: KEVIN LEHMANN] | |
|
4:00 PM, Room 304 Note Special Time |
UNIVERSITY OF CALIFORNIA-BERKELEY | |
| Chemistry Building | “EXPLORING ENZYMATIC ENERGY LANDSCAPE WITH SINGLE-MOLECULE SPECTROSCOPY” |
| I use single-molecule optical microscopy to address a fundamental question in molecular biology: how does protein’s sequence encode its conformational dynamics and function? The model system that we study is the enzyme adenylate kinase (AK) from Escherichia coli. AK’s lid domain undergoes a large conformational change at the catalytic, millisecond timescale, which leads to a reasonable assumption that this lid dynamics is involved in AK’s enzymatic function; yet, its mechanistic roles and energetics remain elusive. Using the high-resolution time-dependent single-molecule FRET (Förster Resonance Energy Transfer) developed in our group, we have measured AK's lid movements on the millisecond scale and map out its entire conformational distribution along the FRET coordinate without a presumed model. Using these new pieces of information, we have quantitatively recovered AK's energetic landscape and related its stochastic lid dynamics to its catalytic function. Finally, the relationship between AK’s genetic coding and its catalytic function is experimentally established by introducing targeted mutation on specific AK sites. This study provides new perspectives on protein engineering. |
|
Friday, May 15, 2009 Note Special Day |
Andreas Buchleitner [Host: Tom Gallagher] | |
|
4:00 PM, Room 204 Note Special Time |
University of Freiburg | |
| Physics Building | “Entanglement in Open Quantum Systems” |
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