A5007211155- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Quantum optics and atomic interactions
- Mechanical and Optical Resonators
- Scientific Measurement and Uncertainty Evaluation
- Quantum Information and Cryptography
- Quantum Mechanics and Applications
- Parallel Computing and Optimization Techniques
- Experimental and Theoretical Physics Studies
- Multilingual Education and Policy
- Distributed and Parallel Computing Systems
- Spanish Linguistics and Language Studies
- Geophysics and Sensor Technology
- Particle Detector Development and Performance
- Atomic and Molecular Physics
- Human Resource Development and Performance Evaluation
- Gas Dynamics and Kinetic Theory
- Laser-induced spectroscopy and plasma
- Linguistic Variation and Morphology
University of Southampton
2017-2023
Queensland Rail
2023
Laboratoire Photonique, Numérique et Nanosciences
2020
Université de Bordeaux
2020
Centre National de la Recherche Scientifique
2020
University of Washington
2017
Abstract Atom-interferometric quantum sensors could revolutionize navigation, civil engineering, and Earth observation. However, operation in real-world environments is challenging due to external interference, platform noise, constraints on size, weight, power. Here we experimentally demonstrate that tailored light pulses designed using robust control techniques mitigate significant error sources an atom-interferometric accelerometer. To mimic the effect of unpredictable lateral motion,...
Abstract We present the theoretical design and experimental implementation of mirror beamsplitter pulses that improve fidelity atom interferometry increase its tolerance systematic inhomogeneities. These are designed using GRAPE optimal control algorithm demonstrated experimentally with a cold thermal sample 85 Rb atoms. first show stimulated Raman inversion pulse achieves ground hyperfine state transfer efficiency 99.8(3)%, compared conventional π 75(3)%. This is robust to variations in...
Atom matterwave interferometry requires mirror and beam splitter pulses that are robust to inhomogeneities in field intensity, magnetic environment, atom velocity, Zeeman substate. We present theoretical results which show pulse shapes determined using quantum control methods can significantly improve interferometer performance by allowing broader distributions, larger areas, higher contrast. have applied gradient ascent engineering (grape) optimize the design of phase-modulated for a...
We present designs for the augmentation ``mirror'' pulses of large-momentum-transfer atom interferometers that maintain their fidelity as wave-packet momentum difference is increased. These biselective pulses, tailored using optimal control methods to evolving bimodal distribution, should allow greater interferometer areas and hence increased inertial measurement sensitivity, without requiring elevated Rabi frequencies or extended frequency chirps. Using an experimentally validated model, we...
Experiments in Atomic, Molecular, and Optical (AMO) physics require precise accurate control of digital, analog, radio frequency (RF) signals. We present hardware based on a field programmable gate array core that drives various modules via simple interface bus. The system supports an operating 10 MHz memory depth 8 M (223) instructions, both easily scalable. Successive experimental sequences can be stacked with no dead time synchronized external events at any instructions. Two or more units...
The authors demonstrate an efficient protocol relying on gray molasses to load rubidium atoms in a telecom optical trap. They further exploit the large AC Stark shift of excited level light assisted, high-speed cooling trap without atom loss.
We present a methodology for the design of optimal Raman beam-splitter pulses suitable cold atom inertial sensors. The methodology, based on time-dependent perturbation theory, links control and sensitivity function formalism in Bloch sphere picture, thus providing geometric interpretation optimization problem. Optimized pulse waveforms are found to be more resilient than conventional ensure near-flat superposition phase range detunings approaching Rabi frequency. As practical application,...
We present an elegant application of matter-wave interferometry to the velocimetry cold atoms whereby, in analogy Fourier transform spectroscopy, one-dimensional velocity distribution is manifest frequency domain interferometer output. By using stimulated Raman transitions between hyperfine ground states perform a three-pulse sequence, we have measured distributions clouds freely expanding $^{85}\mathrm{Rb}$ with temperatures 34 and $18\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{K}$....
Quantum sensors based on cold atoms have enormous potential to unlock new capabilities in GPS-denied navigation, civil engineering, intelligence, and Earth observation. But operating these devices realistic environments is currently extremely challenging, for the most part advantages of choosing a quantum sensor over conventional alternative are lost transition from laboratory noisy field-based environments. In this work, we demonstrate first time hardware that tailored light pulses,...
We consider the matterwave interferometric measurement of atomic velocities, which forms a building block for all inertial measurements. A theoretical analysis, addressing both laboratory and frames accounting residual Doppler sensitivity in beamsplitter recombiner pulses, is followed by an experimental demonstration, with measurements velocity distribution within 20 μK cloud rubidium atoms. Our experiments use Raman transitions between long-lived ground hyperfine states, allow quadrature...
By means of a matched-guise study, this paper examines the attitudes L2, heritage, and native Spanish speakers in state Washington toward Mexican-accented English-accented Spanish. We interpret our findings wake previous research on language ideologies related to United States which shows that those who speak it as first or heritage are thought have lower socioeconomic status than English Anglophones. 97 Spanish-speaking participants residing (N=95) Pacific Northwest (N=2) rated 4 voices...
Abstract Atom interferometers that employ atoms in superpositions of different electronic states are sensitive to any noise affects these superposed differently. Resilience such results from using where the atomic differ momentum only, but implementation ‘state-symmetric’ diffraction can lead population loss into unwanted and restricts velocity acceptance interferometer. In this paper, by varying laser intensities phases as functions time, we present optimized pulses designed for use...
The sensitivity of atom interferometers depends on the fidelity light pulses used as beamsplitters and mirrors. Atom typically employ that affect π/2 π fractional Rabi oscillations, fidelities which are reduced when there variations in atomic velocity laser intensity. We have previously demonstrated application optimal control theory to design more robust such errors; however, if these exhibit a time dependence over periods order interferometer duration then phase shifts can be introduced...
We present a methodology for the design of optimal Raman beam-splitter pulses suitable cold atom inertial sensors. The methodology, based on time-dependent perturbation theory, links control and sensitivity function formalism in Bloch sphere picture, thus providing geometric interpretation optimization problem. Optimized pulse waveforms are found to be more resilient than conventional ensure near-flat superposition phase range detunings approaching Rabi frequency. As practical application,...
Interferometric measurement of an atom's velocity allows, by tailoring the impulse imparted matterwave-splitting laser pulses, a velocity-dependent force that cools atomic sample. Differential reveals sample's acceleration and rotation.