A5047195517- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Quantum Information and Cryptography
- Quantum Mechanics and Applications
- Advanced Electron Microscopy Techniques and Applications
- Quantum optics and atomic interactions
- Scientific Measurement and Uncertainty Evaluation
- Electron and X-Ray Spectroscopy Techniques
- Laser-Matter Interactions and Applications
- Geophysics and Sensor Technology
- Mechanical and Optical Resonators
- Advanced Fluorescence Microscopy Techniques
- Quantum, superfluid, helium dynamics
- Integrated Circuits and Semiconductor Failure Analysis
- Advanced Materials Characterization Techniques
- Photonic and Optical Devices
- Near-Field Optical Microscopy
- Spectroscopy and Laser Applications
- Radioactive Decay and Measurement Techniques
- Pulsars and Gravitational Waves Research
- Advanced Optical Sensing Technologies
- Laser-Plasma Interactions and Diagnostics
- Force Microscopy Techniques and Applications
- Digital Holography and Microscopy
Stanford University
2016-2025
Palo Alto University
2017-2022
Centre for Quantum Technologies
2017
National University of Singapore
2017
AOSense (United States)
2007-2012
Stanford Medicine
2011
Max Planck Institute of Quantum Optics
2009
Hunter College
2007
City University of New York
2007
Simon Fraser University
2007
Interference of atomic de Broglie waves tunneling from a vertical array macroscopically populated traps has been observed. The were located in the antinodes an optical standing wave and loaded Bose-Einstein condensate. Tunneling was induced by acceleration due to gravity, interference observed as train falling pulses atoms. In limit weak interactions, pulse frequency is determined gravitational potential energy difference between adjacent wells. effect closely related ac Josephson...
The mechanical effects of stimulated Raman transitions on atoms have been used to demonstrate a matter-wave interferometer with laser-cooled sodium atoms. Interference has observed for wave packets that separated by as much 2.4 mm. Using the an inertial sensor, acceleration atom due gravity measured resolution 3\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}6}$ after 1000 sec integration time.
We report manipulation of the atom number statistics associated with Bose-Einstein condensed atoms confined in an array weakly linked mesoscopic traps. used interference released from traps as a sensitive probe these statistics. By controlling relative strengths tunneling rate between and atom-atom interactions within each trap, we observed trap states characterized by sub-Poissonian fluctuations adiabatic transitions number-squeezed coherent field. The quantum produced this work may enable...
We report the demonstration of a Sagnac-effect atom interferometer gyroscope which uses stimulated Raman transitions to coherently manipulate atomic wave packets. have measured Earth's rotation rate, and demonstrated short-term sensitivity rotations $2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}(\mathrm{rad}/\mathrm{s})/\sqrt{\mathrm{Hz}}$.
We show that one can ascertain the presence of an object in some sense without interacting with it. One repeatedly, but weakly, tests for object, which would inhibit otherwise coherent evolution interrogating photon. The fraction ``interaction-free'' measurements be arbitrarily close to 1. Using single photons a Michelson interferometer, we have performed preliminary demonstration these ideas.
We report the demonstration of a sensitive absolute-gravity gradiometer based on light-pulse atom-interference techniques. The consists two absolute accelerometers operated in differential mode. acceleration sensitivity $4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}g/{\mathrm{Hz}}^{1/2}$ and an inferred accuracy less than ${10}^{\ensuremath{-}9}g.$ This corresponds to gravity-gradient $4E/{\mathrm{Hz}}^{1/2}$ ${(1E=10}^{\ensuremath{-}9}{\mathrm{s}}^{\mathrm{\ensuremath{-}}2})$...
We measured the Newtonian constant of gravity, G , using a gravity gradiometer based on atom interferometry. The measures differential acceleration two samples laser-cooled Cs atoms. change in gravitational field along one dimension is when well-characterized Pb mass displaced. Here, we report value = 6.693 × 10 –11 cubic meters per kilogram second squared, with standard error mean ±0.027 and systematic ±0.021 squared. possibility that unknown errors still exist traditional measurements...
We report a source of free electron pulses based on field emission tip irradiated by low-power femtosecond laser. The are shorter than 70 fs and originate from with an area diameter down to 2 nm. Depending the operating regime we observe either photofield or optical up 200 electrons per pulse at repetition rate 1 GHz. This pulsed emitter, triggered oscillator, could serve as efficient for time-resolved interferometry, nanometric imaging synchrotrons.
We demonstrate a new cooling technique which is used to cool sodium atoms in one dimension an effective temperature of 100 nK, less than 1/10 the single photon recoil ${\mathit{k}}_{\mathit{B}}$${\mathit{T}}_{\mathrm{rec}}$=(\ensuremath{\Elzxh}k${)}^{2}$/2M.
We reports improvements to our Sagnac effect matter-wave interferometer gyroscope. This device now has a short-term rotation-rate sensitivity of 6×10-10 rad s-1 over 1 s integration, which is the best publicly reported value date. Stimulated Raman transitions are used coherently manipulate atoms from counterpropagating thermal beams, forming two interferometers with opposite rotation phase shifts, allowing be distinguished acceleration and laser arbitrary phase. Furthermore, electronically...
We report the demonstration of an atom interferometer-based gravity gradiometer. The gradiometer uses stimulated two-photon Raman transitions to measure relative accelerations two ensembles laser cooled atoms. have used this instrument gradient Earth's gravitational field.
We show that light-pulse atom interferometry with atomic point sources and spatially resolved detection enables multi-axis (two rotation, one acceleration) precision inertial sensing at long interrogation times. Using this method, we demonstrate a interferometer for Rb-87 1.4 cm peak wavepacket separation duration of 2T = 2.3 seconds. The inferred acceleration sensitivity each shot is 6.7 * 10^(-12) g, which improves on previous limits by more than two orders magnitude. also measure the...
The unprecedented precision of atom interferometry will soon lead to laboratory tests general relativity levels that rival or exceed those reached by astrophysical observations. We propose such an experiment initially test the equivalence principle 1 part in 10(15) (300 times better than current limit), and 10(17) future. It also probe relativistic effects - as nonlinear three-graviton coupling, gravity atom's kinetic energy, falling light several decimals. In contrast with observations, can...
Laser frequency noise is a dominant background for the detection of gravitational waves using long-baseline optical interferometry. Amelioration this requires near simultaneous strain measurements on more than one interferometer baseline, necessitating, example, two satellites space-based detector or arms ground-based detector. We describe new strategy based recent advances in atomic clocks and atom interferometry which can operate at long baselines immune to laser noise. suppressed because...
We propose two distinct atom interferometer gravitational wave detectors, one terrestrial and another satellite based, utilizing the core technology of Stanford 10 m presently under construction. Each configuration compares widely separated interferometers run using common lasers. The signal scales with distance between interferometers, which can be large since only light travels over this distance, not atoms. experiment $\ensuremath{\sim}10\text{ }\text{ }\mathrm{m}$ by a...
Abstract We propose in this White Paper a concept for space experiment using cold atoms to search ultra-light dark matter, and detect gravitational waves the frequency range between most sensitive ranges of LISA terrestrial LIGO/Virgo/KAGRA/INDIGO experiments. This interdisciplinary experiment, called Atomic Experiment Dark Matter Gravity Exploration (AEDGE), will also complement other planned searches exploit synergies with wave detectors. give examples extended sensitivity matter offered...
We demonstrate atom interferometers utilizing a novel beam splitter based on sequential multiphoton Bragg diffractions. With this large momentum transfer (SB-LMT) splitter, we achieve high contrast with splittings of up to 102 photon recoil momenta ($102\ensuremath{\hbar}k$). To our knowledge, is the highest splitting achieved in any interferometer, advancing state-of-the-art by an order magnitude. also strong noise correlation between two simultaneous SB-LMT interferometers, which...
We use a dual-species atom interferometer with 2 s of free-fall time to measure the relative acceleration between ^{85}Rb and ^{87}Rb wave packets in Earth's gravitational field. Systematic errors arising from kinematic differences isotopes are suppressed by calibrating angles frequencies interferometry beams. find an Eötvös parameter η=[1.6±1.8(stat)±3.4(syst)]×10^{-12}, consistent zero violation equivalence principle. With resolution up 1.4×10^{-11} g per shot, we demonstrate sensitivity η...
We present a single-source dual atom interferometer and utilize it as gradiometer for precise gravitational measurements. The macroscopic separation between interfering atomic wave packets (as large 16 cm) reveals the interplay of recoil effects curvature from nearby Pb source mass. baseline is set by laser wavelength pulse timings, which can be measured to high precision. Using long drift time momentum transfer optics, reaches resolution $3 \times 10^{-9}$ s$^{-2}$ per shot measures 1 rad...
Using a matter wave lens and long time of flight, we cool an ensemble Rb87 atoms in two dimensions to effective temperature less than 50−30+50 pK. A short pulse red-detuned light generates optical dipole force that collimates the ensemble. We also report three-dimensional magnetic substantially reduces chemical potential evaporatively cooled ensembles with high atom number. By observing such low temperatures, set limits on proposed modifications quantum mechanics macroscopic regime. These...
Quantum enhanced metrology Exploiting the quantum-mechanical properties of quantum systems offer possibility developing devices for precision measurement and sensing applications. These have, however, required low-noise detection capabilities that have hampered their development. Hosten et al. describe a method manipulates coherent cloud cold rubidium atoms in way relaxes ultrasensitive requirements. The general may be applied to other systems. Science , this issue p. 1552
MAGIS-100 is a next-generation quantum sensor under construction at Fermilab that aims to explore fundamental physics with atom interferometry over 100-meter baseline. This novel detector will search for ultralight dark matter, test mechanics in new regimes, and serve as technology pathfinder future gravitational wave detectors previously unexplored frequency band. It combines techniques demonstrated state-of-the-art 10-meter-scale interferometers the latest technological advances of world's...