A5011784765- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Advanced Fiber Laser Technologies
- Quantum Mechanics and Applications
- Quantum Computing Algorithms and Architecture
- Nonlinear Photonic Systems
- Photonic and Optical Devices
- Advanced Frequency and Time Standards
- Photorefractive and Nonlinear Optics
- Nonlinear Dynamics and Pattern Formation
- Quantum and electron transport phenomena
- Laser-Matter Interactions and Applications
- Orbital Angular Momentum in Optics
- Mechanical and Optical Resonators
- Atomic and Subatomic Physics Research
- Nonlinear Waves and Solitons
- Semiconductor Lasers and Optical Devices
- Magnetic confinement fusion research
- Laser-induced spectroscopy and plasma
- Spectroscopy and Quantum Chemical Studies
- Atomic and Molecular Physics
- Electronic and Structural Properties of Oxides
- Liquid Crystal Research Advancements
- Neural Networks and Reservoir Computing
University of Wisconsin–Madison
2016-2025
IBM Research - Thomas J. Watson Research Center
2023
University of Waterloo
2023
ColdQuanta, Inc., DBA Infleqtion (United States)
2019-2022
Fairchild Semiconductor (United States)
2022
University of Strathclyde
2016
Saarland University
2016
University of Wisconsin System
2006
Australian National University
2004
Technical Products Incorporation (United States)
2004
Rydberg atoms with principal quantum number $n⪢1$ have exaggerated atomic properties including dipole-dipole interactions that scale as ${n}^{4}$ and radiative lifetimes ${n}^{3}$. It was proposed a decade ago to take advantage of these implement gates between neutral atom qubits. The availability strong long-range interaction can be coherently turned on off is an enabling resource for wide range information tasks stretching far beyond the original gate proposal. enabled capabilities include...
We present the first demonstration of a CNOT gate between two individually addressed neutral atoms. Our implementation uses Rydberg blockade interactions atoms held in optical traps separated by >8 microm. Using different protocols we measure fidelities F=0.73 and 0.72 based on truth table probabilities. The was used to generate Bell states with fidelity F=0.48+/-0.06. After correcting for atom loss obtain an posteriori entanglement F=0.58.
We present a review of quantum computation with neutral atom qubits. After an overview architectural options and approaches to preparing large qubit arrays we examine Rydberg mediated gate protocols fidelity for two- multi-qubit interactions. Quantum simulation dressing are alternatives circuit based computing exploring many body dynamics. the properties interaction provide quantitative figure merit complexity coherent dynamics that can be accessed dressing. conclude summary current status...
We demonstrate high fidelity two-qubit Rydberg blockade and entanglement on a pair of sites in large two-dimensional qubit array. The array is defined by grid blue detuned lines light with 121 for trapping atomic qubits. Improved experimental methods have increased the observed Bell state to F_{Bell}=0.86(2). Accounting errors preparation measurement we infer F_{Bell}^{-SPAM}=0.88. single operations that created mediated C_{Z} gate has F_{Bell}^{C_{Z}}=0.89. Comparison detailed error model...
We characterize single-qubit Clifford gate operations with randomized benchmarking in a 2D array of neutral-atom qubits and demonstrate global site selected gates high fidelity. An average fidelity F2=0.9983(14) is measured for microwave-driven applied to 49-qubit array. Single-site are implemented focused laser beam Stark shift the microwaves into resonance at site. At single sites we observe F2=0.9923(7) an spin-flip crosstalk error other 0.002(9).
We present experimental results on two-qubit Rydberg blockade quantum gates and entanglement in a two-dimensional qubit array. Without post selection against atom loss we achieve Bell state fidelity of $0.73\pm 0.05$, the highest value reported to date. The experiments are performed an array single Cs qubits with site spacing $3.8 ~ \mu\rm m$. Using standard protocol for C$_Z$ gate together operations create states measure their using parity oscillations. analyze role AC Stark shifts that...
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Contribution:</i> A roadmap is provided for building a quantum engineering education program to satisfy U.S. national and international workforce needs. xmlns:xlink="http://www.w3.org/1999/xlink">Background:</i> The rapidly growing information science (QISE) industry will require both quantum-aware quantum-proficient engineers at the bachelor's level....
We analyze the effects of Zeeman degeneracies on long-range interactions between like Rydberg atoms, with particular emphasis applications to quantum-information processing using van der Waals blockade. present a general analysis how affect primary error sources in blockade experiments, emphasizing that errors are sensitive primarily weakest possible atom-atom degenerate states, not mean interaction strength. explicit calculations potentials limit where fine-structure is large compared...
We present a detailed analysis and design of neutral atom quantum logic device based on atoms in optical traps interacting via dipole-dipole coupling Rydberg states. The dominant physical mechanisms leading to decoherence loss fidelity are enumerated. Our results support the feasibility performing single two-qubit gates at MHz rates with probability errors level $10^{-3}$ for each operation. Current limitations possible approaches further improvement discussed.
We discuss the application of dipole blockade techniques for preparation single-atom and single-photon sources. A deterministic protocol is given loading a single atom in an optical trap, as well ejecting controlled number atoms desired direction. source with optically beamlike emission pattern described.
We demonstrate Rabi oscillations of small numbers $^{87}\mathrm{Rb}$ atoms between ground and Rydberg states with $n\ensuremath{\le}43$. Coherent population are observed for single atoms, while the presence two or more decoheres oscillations. show that these observations consistent van der Waals interactions atoms.
We demonstrate the deterministic entanglement of two individually addressed neutral atoms using a Rydberg blockade mediated controlled-not gate. Parity oscillation measurements reveal Bell state fidelity $F=0.58\ifmmode\pm\else\textpm\fi{}0.04$, which is above threshold $F=0.5$, without any correction for atom loss, and $F=0.71\ifmmode\pm\else\textpm\fi{}0.05$ after correcting background collisional losses. The results are shown to be in good agreement with detailed error model.
We show that ballistic transport of optically excited atoms in an atomic vapor provides a nonlocal nonlinearity which stabilizes the propagation vortex beams and higher order modes presence self-focusing nonlinearity. Numerical experiments demonstrate stable nonlinear states (dipole, vortices, rotating azimuthons) over hundred diffraction lengths, before dissipation leads to decay these structures.
We demonstrate Rabi flopping at MHz rates between ground hyperfine states of neutral $^{87}$Rb atoms that are trapped in two micron sized optical traps. Using tightly focused laser beams we high fidelity, site specific rotations with crosstalk on neighboring sites separated by $8 \mu\rm m$ the level $10^{-3}$. Ramsey spectroscopy is used to measure a dephasing time $870 s$ which $\approx$ 5000 times longer than for $\pi/2$ pulse.
We propose a new physical approach for encoding and processing of quantum information in ensembles multilevel systems, where the different bits are not carried by individual particles but associated with collective population internal levels. One- two-bit gates implemented state transitions taking place presence an excitation blockade mechanism, which restricts each to values zero unity. Quantum computers 10--20 can be built via this scheme single trapped clouds ground atoms subject Rydberg...
We present an efficient method for producing $N$ particle entangled states using Rydberg blockade interactions. Optical excitation of that interact weakly, yet have a strong coupling to second control state is used achieve dependent qubit rotations in small ensembles. On the basis quantitative calculations we predict N=8 Schr\"odinger cat can be produced with fidelity 84% cold Rb atoms.
With their hyperfine states serving as two-level qubits, atoms can be packed into closely spaced, laser-cooled arrays and individually addressed using laser pulses.
We propose and analyze an approach for preparation of high fidelity entanglement antiferromagnetic states using Rydberg mediated interactions with dissipation. Using asymmetric the two-atom Bell singlet is a dark state pumping process. Master equation simulations demonstrate $\mcF=0.998$. Antiferromagnetic are generated on four spin plaquette in agreement results found from diagonalization transverse field Ising Hamiltonian.
We propose a scheme for the creation of stable three-dimensional bright solitons in Bose-Einstein condensates, i.e., matter-wave analog so-called spatiotemporal ``light bullets.'' Off-resonant dressing to Rydberg $nD$ states is shown provide nonlocal attractive interactions, leading self-trapping mesoscopic atomic clouds by collective excitation atom pair. present detailed potential calculations and demonstrate existence under realistic experimental conditions means numerical simulations.
We propose a two-qubit gate for neutral atoms in which one of the logical state components adiabatically follows two-atom dark formed by laser coupling to Rydberg and strong, resonant dipole-dipole exchange interaction between two excited atoms. Our exhibits optimal scaling intrinsic error probability $E \propto (B\tau)^{-1}$ with interatomic strength $B$ lifetime $\tau$. Moreover, is resilient variations strength, even finite double excitation, does not excite atomic motion experiences no...
We demonstrate |W⟩ state encoding of multiatom ensemble qubits. Using optically trapped Rb atoms, the T_{2} coherence time is 2.6(3) ms for N[over ¯]=7.6 atoms and scales approximately inversely with number atoms. Strong Rydberg blockade between two qubits demonstrated a fidelity 0.89(1), ∼1.0 when postselected on control excitation. These results are significant step towards deterministic entanglement atomic ensembles.
Quantum transduction, the process of converting quantum signals from one form energy to another, is an important area science and technology. The present perspective article reviews transduction between microwave optical photons, that has recently seen a lot activity progress because its relevance for connecting superconducting processors over long distances, among other applications. Our review covers leading approaches achieving such with emphasis on those based atomic ensembles,...