A5058369122- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Quantum and electron transport phenomena
- Quantum optics and atomic interactions
- Advancements in Semiconductor Devices and Circuit Design
- Quasicrystal Structures and Properties
- Random lasers and scattering media
- Quantum Mechanics and Applications
- Atomic and Subatomic Physics Research
- Advanced Chemical Physics Studies
- Molecular spectroscopy and chirality
- Parallel Computing and Optimization Techniques
- Quantum, superfluid, helium dynamics
- Mechanical and Optical Resonators
- Laser-Matter Interactions and Applications
- Orbital Angular Momentum in Optics
- Archaeology and Rock Art Studies
- High-pressure geophysics and materials
- Physics of Superconductivity and Magnetism
- Spectroscopy Techniques in Biomedical and Chemical Research
- Quantum many-body systems
- Force Microscopy Techniques and Applications
- Quantum-Dot Cellular Automata
- Mineralogy and Gemology Studies
- Spectroscopy and Quantum Chemical Studies
Paris Centre for Quantum Technologies
2025
Amazon (United States)
2023-2024
Yale University
2018-2023
California Institute of Technology
2022-2023
University of Chicago
2023
Duke University
2016
Kiel University
2016
An architectural analysis for a fault-tolerant quantum computer is thoroughly presented: With 1,000 superconducting circuit components, problems currently intractable classical computers could be solved.
Quantum error correction with erasure qubits promises significant advantages over standard due to favorable thresholds for errors. To realize this advantage in practice requires a qubit which nearly all errors are such errors, and the ability check without dephasing qubit. We demonstrate that “dual-rail qubit” consisting of pair resonantly coupled transmons can form highly coherent qubit, where transmon <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...
To solve problems of practical importance1,2, quantum computers probably need to incorporate error correction, in which a logical qubit is redundantly encoded many noisy physical qubits3–5. The large physical-qubit overhead associated with correction motivates the search for more hardware-efficient approaches6–18. Here, using superconducting circuit19, we realize memory formed from concatenation bosonic cat qubits an outer repetition code distance d = 5 (ref. 10). A stabilizing circuit...
Hybrid quantum systems in which acoustic resonators couple to superconducting qubits are promising information platforms. High quality factors and small mode volumes make modes ideal memories, while the qubit-phonon coupling enables initialization manipulation of states. We present a scheme for computing with multimode systems, based on this scheme, propose hardware-efficient implementation random access memory (QRAM). Quantum is stored high-Q phonon modes, couplings between engineered by...
Quantum random access memory (QRAM)—memory which stores classical data but allows queries to be performed in superposition—is required for the implementation of numerous quantum algorithms. While naive implementations QRAM are highly susceptible decoherence and hence not scalable, it has been argued that bucket-brigade architecture [Giovannetti et al., Phys. Rev. Lett. 100, 160501 (2008)] is resilient noise, with infidelity a query scaling only logarithmically size. In prior analyses,...
The anticipated applications of quantum computers span across science and industry, ranging from chemistry many-body physics to optimization, finance, machine learning. Proposed solutions in these areas typically combine multiple algorithmic primitives into an overall algorithm, which must then incorporate the methods error correction fault tolerance be implemented correctly on hardware. As such, it can difficult assess how much a particular application benefits computing, as various...
In a recent publication [S. Groth et al., Phys. Rev. B 93, 085102 (2016)], we have shown that the combination of two complementary quantum Monte Carlo approaches, namely configuration path integral [T. Schoof Lett. 115, 130402 (2015)] and permutation blocking Dornheim New J. 17, 073017 (2015)], allows for accurate computation thermodynamic properties spin-polarized uniform electron gas over wide range temperatures densities without fixed-node approximation. present work, extend this concept...
We draw analogies between protected superconducting qubits and bosonic by studying the fluxonium Hamiltonian in its Fock basis. The mean-field phase diagram of (at sweet spot) is identified, with a region parameter space that characterized $\mathbb{Z}_2$-symmetry-broken ground states. In heavy limit, these states are well approximated squeezed coherent basis (corresponding to persistent current definite flux but indefinite charge), simple expressions provided for them terms circuit...
Cat qubits, a type of bosonic qubit encoded in harmonic oscillator, can exhibit an exponential noise bias against bit-flip errors with increasing mean photon number. Here, we focus on cat qubits stabilized by two-photon dissipation, where pairs photons are added and removed from oscillator auxiliary, lossy buffer mode. This process requires large loss rate strong nonlinearities the mode that must not degrade coherence linearity oscillator. In this work, show how to overcome challenge...
In this paper we propose the Quantum Data Center (QDC), an architecture combining Random Access Memory (QRAM) and quantum networks. We give a precise definition of QDC discuss its possible realizations extensions. applications in computation, communication, sensing, with primary focus on for $T$-gate resources, multiparty private distributed sensing through data compression. show that will provide efficient, private, fast services as future version centers.
Qubit measurements are central to quantum information processing. In the field of superconducting qubits, standard readout techniques not only limited by signal-to-noise ratio, but also state relaxation during measurement. this work, we demonstrate that limitation due can be suppressed using many-level Hilbert space circuits: in a multilevel encoding, measurement is corrupted when multiple errors occur. Employing technique, show directly resolve transmon gate at level one part $10^3.$...
Operating on the principles of quantum mechanics, algorithms hold promise for solving problems that are beyond reach best-available classical algorithms. An integral part realizing such speedup is implementation queries, which read data into forms computers can process. Quantum random access memory (QRAM) a promising architecture queries. However, implementing QRAM in practice poses significant challenges, including query latency, capacity and fault-tolerance.
Single-photon detectors are ubiquitous and integral components of photonic quantum cryptography, communication, computation. Many applications, however, require not only detecting the presence any photons, but distinguishing number present with a single shot. Here, we implement single-shot, high-fidelity photon number-resolving detector up to 15 microwave photons in cavity-qubit circuit QED platform. This functions by measuring series generalized parity operators which make bits binary...
High-fidelity qubit measurements play a crucial role in quantum computation, communication, and metrology. In recent experiments, it has been shown that readout fidelity may be improved by performing repeated non-demolition (QND) readouts of qubit's state through an ancilla. For encoded two-level system, the such schemes is limited fact single error can destroy information qubit. On other hand, if bosonic system used, this fundamental limit could overcome utilizing higher levels still leaves...
Icosahedral quasicrystals (IQCs) with extremely high degrees of translational order have been produced in the laboratory and found naturally occurring minerals, yet questions remain about how IQCs form. In particular, fundamental question locally determined additions to a growing cluster can lead intricate long-range correlations remains open. answer this question, we developed an algorithm that is capable producing perfectly ordered IQC, relies exclusively on local rules for sequential,...
Efficient suppression of errors without full error correction is crucial for applications with noisy intermediate-scale quantum devices. Error mitigation allows us to suppress in extracting expectation values the need any code, but its are limited estimating values, and cannot provide high-fidelity operations acting on arbitrary states. To address this challenge, we propose use filtration (EF) gate-based computation, as a practical scheme resorting correction. The result general-purpose...
In order to solve problems of practical importance, quantum computers will likely need incorporate error correction, where a logical qubit is redundantly encoded in many noisy physical qubits. The large physical-qubit overhead typically associated with correction motivates the search for more hardware-efficient approaches. Here, using microfabricated superconducting circuit, we realize memory formed from concatenation bosonic cat qubits an outer repetition code distance $d=5$. are passively...
Cat qubits, a type of bosonic qubit encoded in harmonic oscillator, can exhibit an exponential noise bias against bit-flip errors with increasing mean photon number. Here, we focus on cat qubits stabilized by two-photon dissipation, where pairs photons are added and removed from oscillator auxiliary, lossy buffer mode. This process requires large loss rate strong nonlinearities the mode that must not degrade coherence linearity oscillator. In this work, show how to overcome challenge...
In this paper, we propose the Quantum Data Center (QDC), an architecture combining Random Access Memory (QRAM) and quantum networks. We give a precise definition of QDC, discuss its possible realizations extensions. applications QDC in computation, communication, sensing, with primary focus on for $T$-gate resources, multi-party private distributed sensing through data compression. show that will provide efficient, private, fast services as future version centers.
We take a bottom-up first-principles approach to designing two-qubit gate between fluxonium qubits for minimal error, speed, and control simplicity. Our proposed architecture consists of two fluxoniums coupled via resonator. The use simple linear coupler has many practical benefits, including the possibility material optimization suppressing loss, reducing fabrication complexity, increasing yield by circumventing need Josephson junctions. Crucially, resonator-as-coupler also suggests clear...
We take a bottom-up, first-principles approach to design two-qubit gate between fluxonium qubits for minimal error, speed, and control simplicity. Our proposed architecture consists of two fluxoniums coupled via linear resonator. Using coupler introduces the possibility material optimization suppressing its loss, enables efficient driving state-selective transitions through large charge zero point fluctuation, reduces sensitivity junction aging, partially mitigates coherent coupling...
The conditional displacement (CD) gate between an oscillator and a discrete-variable ancilla plays key role in quantum information processing tasks, such as enabling universal control of the longitudinal readout qubit. However, is unprotected against propagation decay errors hence not fault-tolerant. Here, we propose CD scheme with fluxonium ancilla, which has been experimentally demonstrated to have large noise bias millisecond-level lifetimes. proposed applied cross-resonantly by...
Dissipative cat qubits are a promising physical platform for quantum computing, since their large noise bias can enable more hardware-efficient error correction. In this work we theoretically study the long-term prospects of hybrid cat-transmon computing architecture where dissipative play role data qubits, and syndromes measured using ancillary transmon qubits. The qubits' enables correction, use transmons allows practical, high-fidelity syndrome measurement. While correction dominant Z...