A5087631326- Quantum optics and atomic interactions
- Quantum Information and Cryptography
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Computing Algorithms and Architecture
- Advanced Frequency and Time Standards
- Quantum and electron transport phenomena
- Quantum many-body systems
- Nonlinear Dynamics and Pattern Formation
- Mechanical and Optical Resonators
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Theoretical and Computational Physics
- Physics of Superconductivity and Magnetism
- Quantum Mechanics and Applications
- Magnetic properties of thin films
- Neural Networks and Reservoir Computing
- Metallic Glasses and Amorphous Alloys
- Atomic and Molecular Physics
- Characterization and Applications of Magnetic Nanoparticles
- Quantum, superfluid, helium dynamics
- Laser Design and Applications
- Quantum chaos and dynamical systems
- nanoparticles nucleation surface interactions
- Spectroscopy and Quantum Chemical Studies
Honeywell (United States)
2020-2022
National Institute of Standards and Technology
2012-2019
Joint Institute for Laboratory Astrophysics
2011-2018
University of Colorado Boulder
2011-2017
University of Northern Iowa
2007-2010
Quantum simulation of spin models can provide insight into complex problems that are difficult or impossible to study with classical computers. Trapped ions an established platform for quantum simulation, but only systems fewer than 20 have demonstrated correlations. Here we non-equilibrium, dynamics arising from engineered, homogeneous Ising interaction in a two-dimensional array $^9$Be$^+$ Penning trap. We verify entanglement the form spin-squeezed states up 219 ions, directly observing...
We use the vacuum Rabi splitting to perform quantum nondemolition (QND) measurements that prepare a conditionally spin-squeezed state of collective atomic psuedo-spin. infer 3.4(6) dB improvement in phase estimation relative standard limit for coherent spin composed uncorrelated atoms. The measured is two-level clock states nearly 10^6 Rb-87 atoms confined inside low finesse F = 710 optical cavity. This technique may improve sensor precision and/or bandwidth, and lead more precise tests...
We use a self-assembled two-dimensional Coulomb crystal of $\sim 70$ ions in the presence an external transverse field to engineer simulator Dicke Hamiltonian, iconic model quantum optics which features phase transition between superradiant/ferromagnetic and normal/paramagnetic phase. experimentally implement slow quenches across critical point benchmark dynamics performance through extensive theory-experiment comparisons show excellent agreement. The implementation fully controllable...
We experimentally study electromagnetically induced transparency cooling of the drumhead modes planar two-dimensional arrays with up to N≈190 Be^{+} ions stored in a Penning trap. Substantial sub-Doppler is observed for all N modes. Quantitative measurements center-of-mass mode show near ground-state motional quantum numbers n[over ¯]=0.3±0.2 obtained within 200 μs. The measured rate faster than that predicted by single particle theory, consistent many-body calculation. For lower frequency...
Correcting errors in real-time is essential for reliable large-scale quantum computations. Realizing this high-level function requires a system capable of several low-level primitives, including single-qubit and two-qubit operations, mid-circuit measurements subsets qubits, processing measurement outcomes, the ability to condition subsequent gate operations on those measurements. In work, we use ten qubit QCCD (quantum charge-coupled device) trapped-ion computer encode single logical using...
Probing the collective spin state of an ensemble atoms may provide a means to reduce heating via photon recoil associated with measurement and robust, scalable route for preparing highly entangled states spectroscopic sensitivity below standard quantum limit coherent states. The probing relies on obtaining very large optical depth that can be effectively increased by placing within cavity such probe light passes many times through ensemble. Here we expressions resolution enhancement in...
We experimentally demonstrate synchronization between two distinct ensembles of cold atoms undergoing steady state superradiance within a single longitudinal and transverse mode the same optical cavity. The process is studied first in terms time dynamics re-synchronization when phase alignment oscillators abruptly broken. also observe behavior lasers as their relative frequency continuously varied. This system has potential to realize non-equilibrium quantum transition could inform future...
We introduce a bang-bang shortcut to adiabaticity for the Dicke model, which we implement via 2-D array of trapped ions in Penning trap with spin-dependent force detuned close center-of-mass drumhead mode. Our focus is on employing this create highly entangled states that can be used high-precision metrology. highlight performance approach comparable standard preparation methods, but applied over much shorter time frame. compare these theoretical ideas experimental data serve as first step...
We experimentally study the relaxation oscillations and amplitude stability properties of an optical laser operating deep into bad-cavity regime using a laser-cooled $^{87}$Rb Raman laser. By combining measurements light field with nondemolition atomic populations, we infer response gain medium represented by collective Bloch vector. The results are qualitatively explained simple model. Measurements theory extended to include effect intermediate repumping states on closed-loop oscillator...
We study the nondemolition mapping of collective quantum coherence onto a cavity light field in superradiant, cold-atom ${}^{87}$Rb Raman laser. show theoretically that fundamental precision is near standard limit on phase estimation for coherent spin state, $\ensuremath{\Delta}\ensuremath{\phi}=1/\sqrt{N}$, where $N$ number atoms. The associated characteristic measurement time scale ${\ensuremath{\tau}}_{W}\ensuremath{\propto}1/N$ collectively enhanced. nature characterized by only 0.5...
Using analogies from cavity steady-state superradiance, an experimental scheme for mesoscopic collective spin synchronization is proposed with ion-trap systems, where the in primary species of ions mediated by dissipation a normal vibrational mode induced sympathetic cooling secondary ions.
We demonstrate a proof-of-principle magnetometer that relies on the active oscillation of cold atom Raman laser to continuously map field-sensitive atomic phase onto radiated light. wideband sensitivity during continuous oscillation, as well narrowband in passive Ramsey-like mode with translation detection frequency using spin-echo techniques. The sensor operates 190 pT/Hz at 1 kHz and effective sensing volume 2×10−3 mm3. Fundamental quantum limits magnetic field an ideal detector are also...
Quantum manipulation protocols for quantum sensors and computation often require many single qubit rotations. However, the impact of phase noise in field that performs rotations is neglected or treated only special cases. We present a general framework calculating on state qubit, as described by its equivalent Bloch vector. The analysis applies to any vector orientation, rotation axis azimuthal angle both pulse, pulse sequences. Experimental examples are presented several apply commonly used...
We demonstrate photodissociation of BeH$^+$ ions within a Coulomb crystal thousands $^9$Be$^+$ confined in Penning trap. Because are created via exothermic reactions between trapped, laser-cooled Be$^+$($^2\text{P}_{3/2}$) and background H$_2$ the vacuum chamber, they represent major contaminant species responsible for infidelities large-scale trapped-ion quantum information experiments. The rotational-state-insensitive dissociation scheme described here makes use 157 nm photons to produce...
We theoretically study a superradiant laser, deriving both the steady-state behaviors and small-amplitude responses of laser's atomic inversion, polarization, light field amplitude. Our minimum model for three-level laser includes population accumulating outside lasing transition dynamics distribution causing cavity frequency tuning, as can occur in realistic experimental systems. show that act real-time feedback to stabilize or destabilize output power, we derive tuning Raman laser. extend...
Superconducting magnets enable precise control of nuclear and electron spins, are used in experiments that explore biological condensed-matter systems, fundamental atomic particles. In high-precision applications, a common view is slow $(<1\phantom{\rule{4.pt}{0ex}}\mathrm{Hz})$ drift the homogeneous magnetic-field limits measurement precision. We report on previously undocumented higher-frequency field noise (10--200 Hz) coherence time $^{9}\text{Be}^{+}$ electron-spin qubits...
Melt-spun Gd is a structurally inhomogeneous system consisting of crystalline grains with an average size $24\ifmmode\pm\else\textpm\fi{}3\text{ }\text{nm}$ that are separated by amorphous interphase. This exhibits depression ${T}_{C}$ $(289.70\ifmmode\pm\else\textpm\fi{}0.01\text{ }\text{K})$ relative to bulk (293 K). The effective critical exponents (${\ensuremath{\beta}}_{\text{eff}}=0.389\ifmmode\pm\else\textpm\fi{}0.017$,...
We investigate the impact of a rotating wall potential on perpendicular laser cooling in Penning ion trap. By including energy exchange with wall, we extend previous Doppler theory and show that low temperatures are more readily achieved than without. Detailed numerical studies determine optimal operating parameters for producing temperature, stable 2-dimensional crystals, important quantum information processing experiments employing traps.
We propose to build a bad-cavity laser using forbidden transitions in large ensembles of cold ions that form Coulomb crystal linear Paul trap. This might realize an active optical frequency standard able serve as local oscillator next-generation clock schemes. In passive clocks, appear less promising, they suffer from inhomogeneous broadening due quadrupole interactions and micromotion-related shifts. lasers, however, the radiating dipoles can synchronize generate stable narrow-linewidth...
We describe and characterize a simple, low cost, phase noise microwave source that operates near 6.800 GHz for agile, coherent manipulation of ensembles 87Rb. Low is achieved by directly multiplying 100 MHz crystal to 6.8 using non-linear transmission line filtering the output with custom band-pass filters. The fixed frequency signal single sideband modulated direct digital synthesis provide desired phase, amplitude, control. Before modulation, has -140 dBc/Hz in range 10 kHz 1 offset from...