A5083525654- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum and electron transport phenomena
- Quantum optics and atomic interactions
- Mass Spectrometry Techniques and Applications
- Neural Networks and Reservoir Computing
- Radiation Effects in Electronics
- Parallel Computing and Optimization Techniques
- Semiconductor materials and devices
- Advanced Frequency and Time Standards
- Molecular Junctions and Nanostructures
- Atomic and Subatomic Physics Research
- Ion-surface interactions and analysis
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor Quantum Structures and Devices
- Analytical Chemistry and Sensors
- Advanced Semiconductor Detectors and Materials
- Optical Coatings and Gratings
- Photoreceptor and optogenetics research
- Scientific Measurement and Uncertainty Evaluation
- Photorefractive and Nonlinear Optics
- nanoparticles nucleation surface interactions
- Electronic and Structural Properties of Oxides
- Low-power high-performance VLSI design
Georgia Tech Research Institute
2016-2024
Georgia Institute of Technology
2016-2024
University of Maryland, College Park
2012
Joint Quantum Institute
2012
We present a method for accurate determination of atomic transition matrix elements at the ${10}^{\ensuremath{-}3}$ level. Measurements ac Stark (light) shift around ``magic-zero'' wavelengths, where light vanishes, provide precise constraints on elements. make first measurement $5s\ensuremath{-}6p$ in rubidium by measuring 421 and 423 nm zeros through diffraction condensate off sequence standing wave pulses. In conjunction with existing theoretical experimental data, we find...
We study the Quantum Approximate Optimization Algorithm ( QAOA ) in context of Max-Cut problem. Noisy quantum devices are only able to accurately execute at low circuit depths, while classically-challenging problem instances may call for a relatively high circuit-depth. This is due need build correlations between reachable pairs vertices potentially large graphs [ 16 ]. To enhance solving power low-depth QAOA, we introduce classical pre-processing step that initializes with biased...
Using trapped ion quantum bits in a scalable microfabricated surface trap, we perform the Bernstein-Vazirani algorithm. Our architecture relies upon transport and can readily be expanded to larger systems. The algorithm is demonstrated using two- three-ion chains. For three ions, an improvement achieved compared classical system same number of oracle queries. two ions one query, correctly determine unknown bit string with probability 97.6(8)%. succeed 80.9(3)%.
Ion transport is an essential operation in some models of quantum information processing, where fast ion shuttling with minimal motional excitation necessary for efficient, high-fidelity logic. While and cold has been demonstrated, the dynamics specific trajectory during diabatic have not studied detail. Here we describe a position-dependent optical deshelving technique useful sampling ion's position throughout its trajectory, demonstrate on linear $^{40}\text{Ca}^+$ surface-electrode trap....
We demonstrate universal quantum control over chains of ions in a surface-electrode ion trap, including all the fundamental operations necessary to perform algorithms one-dimensional, nearest-neighbor computing architecture. realize both single-qubit and entangling gates with Raman laser beams, we interleave two gate types. report average fidelities as high 0.970(1) for two-, three-, four-ion chains, characterized randomized benchmarking. generate Bell states between pairs three-ion chain,...
We implement individual addressing and readout of ions in a rigidly rotating planar crystal compact, permanent magnet Penning trap. The ^{40}Ca^{+} is trapped stabilized without defects via triangular potential. ion fluorescence detected the frame for parallel readout. qubit encoded metastable D_{5/2} manifold enabling use high-power near-infrared laser systems operations. Addressed σ_{z} operations are realized with focused ac Stark shifting beam. demonstrate near center at large radii....
We study the Quantum Approximate Optimization Algorithm (QAOA) in context of Max-Cut problem. Near-term (noisy) quantum devices are only able to (accurately) execute QAOA at low circuit depths while requires a relatively high circuit-depth order "see" whole graph. introduce classical pre-processing step that initializes with biased superposition all possible cuts graph, referred as warm-start. In particular, our initialization informs by solution low-rank semidefinite programming relaxation...
The robust phase estimation (RPE) protocol was designed to be an efficient and way calibrate quantum operations. robustness of RPE refers its ability estimate a single parameter, usually gate amplitude, even when other parameters are poorly calibrated or the experiences significant errors. Here we demonstrate errors that affect initialization, measurement, gates. In each case, error threshold at which begins fail matches quantitatively with theoretical bounds. We conclude is effective...
We present methods for constructing any target coupling graph using limited global controls in an Ising-like quantum spin system. Our approach is motivated by implementing the approximate optimization algorithm (QAOA) on trapped-ion hardware to find solutions MaxCut. a mathematical description of problem and provide approximately optimal algorithmic constructions that generate arbitrary unweighted graphs with $n$ nodes $O(n)$ entangling operations weighted $m$ edges $O(m)$ operations. These...
Many-qubit M\o{}lmer-S\o{}rensen (MS) interactions applied to trapped ions offer unique capabilities for quantum information processing, with applications including simulation and the approximate optimization algorithm (QAOA). Here, we develop a physical model describe many-qubit MS under four sources of experimental noise: vibrational mode frequency fluctuations, laser power thermal initial states, state preparation measurement errors. The parametrizes these errors from simple measurements,...
We implement individual addressing and readout of ions in a rigidly rotating planar crystal compact, permanent magnet Penning trap. The $^{40}$Ca$^+$ is trapped stabilized without defects via triangular potential. ion fluorescence detected the frame for parallel readout. qubit encoded metastable D$_{5/2}$ manifold enabling use high-power near-infrared laser systems operations. Addressed $\sigma_z$ operations are realized with focused AC Stark shifting beam. demonstrate near center at large...
We analytically solve a model for light scattering in Ising dynamics of metastable atomic qubits, generalizing the approach Foss-Feig {\it et al.}~[Phys.~Rev.~A {\bf 87}, 042101 (2013)] to include leakage outside qubit manifold. analyze influence these fundamental errors simulations proposed experiments with levels $^{40}$Ca$^+$ ions. find that ``effective magnetic fields" generated by leaked qubits have significant impacts on spin-spin correlation functions Greenberger-Horne-Zeilinger state...
We present methods for constructing any target coupling graph using limited global controls in an Ising-like quantum spin system. Our approach is motivated by implementing the approximate optimization algorithm (QAOA) on trapped ion hardware to find solutions Max-Cut. a mathematical description of problem and provide approximately optimal algorithmic constructions that generate arbitrary unweighted graphs with $n$ nodes $O(n)$ entangling operations weighted $m$ edges $O(m)$ operations. These...
Ion trap quantum hardware promises to provide a computational advantage over classical computing for specific problem spaces while also providing an alternative implementation path cryogenic systems as typified by IBM's hardware. However, programming ion currently requires both strategies mitigate high levels of noise and tools ease the challenge these with pulse- or gate-level operations. This work focuses on improving state-of-the-art testbeds through use language specification, QCOR,...
Ion transport is an essential operation in some models of quantum information processing, where fast ion shuttling with minimal motional excitation necessary for efficient, high-fidelity logic. While and cold has been demonstrated, the dynamics specific trajectory during diabatic have not studied detail. Here we describe a position-dependent optical deshelving technique useful sampling ion's position throughout its trajectory, demonstrate on linear $^{40}\text{Ca}^+$ surface-electrode trap....
The 53rd Annual Meeting of the APS Division Atomic, Molecular and Optical Physics will take place from May 30 – June 3, 2022 in Orlando, Fl, USA. <a href="https://morressier.zoom.us/j/89880865272?pwd=SWxTRGhra1ZOSDBrSkhVZDBzVDR6UT09/">Virtual Presenter Help Desk</a>
The 53rd Annual Meeting of the APS Division Atomic, Molecular and Optical Physics will take place from May 30 – June 3, 2022 in Orlando, Fl, USA. <a href="https://morressier.zoom.us/j/89880865272?pwd=SWxTRGhra1ZOSDBrSkhVZDBzVDR6UT09/">Virtual Presenter Help Desk</a>
Many-qubit Mølmer-Sørensen (MS) interactions applied to trapped ions offer unique capabilities for quantum information processing, with applications including simulation and the approximate optimization algorithm (QAOA). Here, we develop a physical model describe many-qubit MS under four sources of experimental noise: vibrational mode frequency fluctuations, laser power thermal initial states, state preparation measurement errors. The parameterizes these errors from simple measurements,...