A5037805974- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Advanced Frequency and Time Standards
- Muon and positron interactions and applications
- Atomic and Molecular Physics
- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Quantum, superfluid, helium dynamics
- Spectroscopy and Laser Applications
- Quantum Mechanics and Applications
- Mechanical and Optical Resonators
- Laser Design and Applications
- Particle accelerators and beam dynamics
- Strong Light-Matter Interactions
- Experimental and Theoretical Physics Studies
- Electronic and Structural Properties of Oxides
- Physics of Superconductivity and Magnetism
- Advanced Thermodynamics and Statistical Mechanics
- Quantum Electrodynamics and Casimir Effect
- Laser-Matter Interactions and Applications
- Quantum and electron transport phenomena
- Particle physics theoretical and experimental studies
- Quantum Computing Algorithms and Architecture
- Orbital Angular Momentum in Optics
- X-ray Spectroscopy and Fluorescence Analysis
Los Alamos National Laboratory
2012-2023
Istituto Nazionale di Fisica Nucleare, Sezione di Catania
2022
Technology Innovation Institute
2022
National University of Singapore
2022
Centre for Quantum Technologies
2022
University of Sussex
1997-2007
Yale University
1991-2002
Sussex County Community College
2000
Heidelberg University
1995
Syracuse University
1995
We have studied the deflection of ground-state sodium atoms passing through a micron-sized parallel-plate cavity by measuring intensity atomic beam transmitted as function plate separation. This experiment provides clear evidence for existence Casimir-Polder force, which is due to modification Lamb shift in confined space cavity. Our results confirm magnitude force and distance dependence predicted quantum electrodynamics.
There is a pressing need for robust and straightforward methods to create potentials trapping Bose–Einstein condensates (BECs) that are simultaneously dynamic, fully arbitrary sufficiently stable not heat the ultracold gas. We show here how accomplish these goals, using rapidly moving laser beam 'paints' time-averaged optical dipole potential in which we BECs variety of geometries, including toroids, ring lattices square lattices. Matter wave interference patterns confirm trapped gas...
We report the creation of a pair Josephson junctions on toroidal dilute gas Bose-Einstein condensate (BEC), configuration that is cold atom analog well-known dc superconducting quantum interference device (SQUID). observe effects, measure critical current junctions, and find dynamic behavior in good agreement with simple equations for tunnel junction ideal sinusoidal current-phase relation expected parameters experiment. The trap are created painted potential, time-averaged optical dipole...
Atomtronics deals with matter-wave circuits of ultracold atoms manipulated through magnetic or laser-generated guides different shapes and intensities. In this way, new types quantum networks can be constructed in which coherent fluids are controlled the know-how developed atomic molecular physics community. particular, devices enhanced precision, control, flexibility their operating conditions accessed. Concomitantly, simulators emulators harnessing on current flows also developed. Here,...
Atomtronics refers to the use of ultracold atoms for building circuits that rely on coherent propagation matter waves in waveguides. While still its infancy, this new quantum technology is promising both applications and probing correlated atomic itself. This Colloquium explains current state field discusses possible applications.
High precision measurements of two Zeeman hyperfine transitions in the ground state muonium a strong magnetic field have been made at LAMPF using microwave resonance spectroscopy and line narrowing technique. These determine most precise values structure interval $\ensuremath{\Delta}\ensuremath{\nu}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}4463302765(53)\mathrm{Hz}$ $(12\mathrm{ppb})$, ratio moments...
Operating a laser diode in an extended cavity which provides frequency-selective feedback is very effective method of reducing the laser’s linewidth and improving its tunability. We have developed extremely simple this type, built from inexpensive commercial components with only few minor modifications. A 780 nm to design has output power 80 mW, 350 kHz, it been continuously locked Doppler-free rubidium transition for several days.
Atomtronics is an emerging field in quantum technology that promises to realize 'atomic circuit' architectures exploiting ultra-cold atoms manipulated versatile micro-optical circuits generated by laser fields of different shapes and intensities or micro-magnetic known as atom chips. Although devising new applications for computation information transfer a defining goal the field, atomtronics wants enlarge scope simulators access physical regimes with novel fundamental science. With this...
We have demonstrated that cold atoms can be retroflected from a ferromagnetic surface by the Stern-Gerlach effect. When is magnetized periodically, reflectivity for suitably polarized $(94\ifmmode\pm\else\textpm\fi{}8)%$ and reflection specular. A demagnetized also highly reflecting but reflections are diffuse. These magnetic processes of interest atom optics because they permit manipulation without use laser beams. In our experiments, Rb released magneto-optic trap (MOT) fall under gravity...
We present a general discussion of the techniques destabilizing dark states in laser-driven atoms with either magnetic field or modulated laser polarization. show that photon scattering rate is maximized at particular evolution state. also find atomic resonance curve significantly broadened when far from this optimum value. These results are illustrated detailed examples some commonly-trapped ions and supported by insights derived numerical calculations simple theoretical models.
A versatile miniature de Broglie waveguide is formed by two parallel current-carrying wires in the presence of a uniform bias field. We derive variety analytical expressions to describe guide and present quantum theory show that it offers remarkable range possibilities for atom manipulation on submicron scale. These include controlled coherent splitting wave function as well cooling, trapping, guiding. In particular, we discuss novel microscopic interferometer with potential be exceedingly sensitive.
An integrated coherent matter wave circuit is a single device, analogous to an optical circuit, in which de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, detected as propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, precisely controlled delivery atoms. Here we report experiments demonstrating for waves. The elements with the painted potential technique, form time-averaged dipole...
Optically pumped magnetometers (OPM) can be used in various applications, from magnetoencephalography to magnetic resonance imaging and nuclear quadrupole (NQR). OPMs provide high sensitivity have the significant advantage of non-cryogenic operation. To date, many been demonstrated with close 1 fT, but most devices are not commercialized. Most recently, QuSpin developed a model OPM that is low cost, sensitivity, convenient for users, which operates single-beam configuration. Here we theory...
Abstract Quantum interference of currents is the most important and well known quantum phenomenon in a conventional superconducting device (SQUID). Here, we report observation an atomtronic SQUID. Analogous to SQUID, flowing through two junctions SQUID interfere due phase difference from rotation. This results modulation critical currents. was observed for three different radii with clear periods which were measured be consistent fundamental rotation rates. shows possibility studying various...
Confining the propagating wave packets of an atom interferometer inside a waveguide can substantially reduce size device while preserving high sensitivity. We have realized two-dimensional Sagnac in which Bose-condensed $^{87}\mathrm{Rb}$ atoms propagate within tight formed by collimated laser beam, matter analog fiber optic gyro. The condensate is split, reflected, and recombined with series Bragg pulses moves transversely so that wave-packet trajectories enclose area. Delta-kick cooling...
The 1s-2s interval has been measured in the muonium (&mgr;(+)e(-)) atom by Doppler-free two-photon pulsed laser spectroscopy. frequency separation of states was determined to be 2 455 528 941.0(9.8) MHz, good agreement with quantum electrodynamics. result may interpreted as a measurement muon-electron charge ratio -1-1.1(2.1)x10(-9). We expect significantly higher accuracy at future high flux muon sources and from cw technology.
We have measured the combination of hydrogen Lamb shifts ${L}_{1S}\ensuremath{-}5{L}_{2S}+4{L}_{4P}$ by comparing frequencies $1S\ensuremath{-}2S$ and $2S\ensuremath{-}4P$ transitions. The measurement determines $1S$ shift to be 8 172 827(51) kHz, most precise value for any shift. theoretical predictions ${L}_{1S}$ are 802(30) 654(40) corresponding proton charge radius values 0.862(12) 0.805(11) fm, respectively.
We formulate a robust optimal control algorithm to synthesize minimum energy pulses that can transfer cold atom system into various momentum states. The uses adaptive linearization of the evolution operator and sequential quadratic programming iterate towards signal achieves target state fidelity. Robustness parameter variation is achieved using Legendre polynomial approximation over domain variation. method applied optimize Bragg beamsplitting operation in ultra-cold interferometry. Even...
We have devised a way to trap atoms above magnetic surface using the Zeeman effect. The method is generally applicable any paramagnetic atom with hyperfine structure and results in very strong confinement and, hence, high vibrational frequency perpendicular surface. This allows atomic de Broglie wave propagate as single-mode 2D waveguide. show how can be continuously unidirectionally coupled efficiency into lowest mode of invention makes possible study weakly interacting gases 2D.
This roadmap bundles fast developing topics in experimental optical quantum sciences, addressing current challenges as well potential advances future research. We have focused on three main areas: assisted high precision measurements, information/simulation, and gases. Quantum measurements are discussed the first sections, which review clocks, atom interferometry, magnetometry. These fields already successfully utilized various applied areas. will discuss approaches to extend this impact...
Bessel beams are plane waves with amplitude profiles described by functions. They important because they propagate 'diffraction-free' and can carry orbital angular momentum. Here we report the creation of a beam de Broglie matter waves. The is produced free evolution thin toroidal atomic Bose–Einstein condensate (BEC) which has been set into rotational motion. By attempting to stir it at different rotation rates, show that BEC only be made rotate discrete, equally spaced frequencies,...
We have imaged an $18\ensuremath{\mu}\mathrm{K}$ cloud of ${}^{85}\mathrm{Rb}$ atoms bouncing freely on a horizontal, concave magnetic atom mirror (radius curvature $R$). A high-quality image is observed even after 14 reflections. Initially compact, the alternately collimated (odd bounces) and brought back to focus (even when dropped from height $R/4$. This multiple reconstruction thermally expanding hinges microscopic reversal atomic motion. discuss factors limiting resolution describe...
We have observed the narrow 1S-2S transition in hydrogen and deuterium with high resolution using Doppler-free two-photon absorption of continuous-wave 243-nm light. The frequencies were measured by direct comparison accurately calibrated lines spectrum $^{130}\mathrm{Te}_{2}$ molecule. find interval to be 2 466 061 414.1(8) MHz 732 408.5(7) deuterium. By combining these results recent measurements Rydberg constant we obtain values 8172.6(7) 8183.7(6) for 1S Lamb shifts deuterium,...
We have shown that the external cavity stabilization can be a straightforward and powerful technique for converting diode lasers of poor spectral quality into useful tools high precision laser spectroscopy. The method requires an anti-reflection coating on one facet but, contrary to popular belief, this is not difficult does require any specialized equipment. describe procedure which used with standard commercial lasers. demonstrated using diodes at variety visible infrared wavelengths....