Simultaneous Operations in a Two-Dimensional Array of Singlet-Triplet Qubits

Abstract

In many physical approaches to quantum computation, error-correction schemes assume the ability to form two-dimensional qubit arrays with nearest-neighbor couplings and parallel operations at multiple qubit sites. While semiconductor spin qubits exhibit long coherence times relative to their operation speed and single-qubit fidelities above error correction thresholds, multiqubit operations in two-dimensional arrays have been limited by fabrication, operation, and readout challenges. We present a two-by-two array of four singlet-triplet qubits in gallium arsenide and show simultaneous coherent operations and four-qubit measurements via exchange oscillations and frequency-multiplexed single-shot measurements. A larger multielectron quantum dot is fabricated in the center of the array as a tunable interqubit link, which we utilize to demonstrate coherent spin exchange with selected qubits. Our techniques are extensible to other materials, indicating a path towards quantum processors with gate-controlled spin qubits.

arXiv commentRevised version after peer review, with additional supporting data. 13 pages, 9 figures (including 4-page 4-figure supplement)

References in corpus (25)

• A Two Qubit Logic Gate in Silicon
• A >99.9%-fidelity quantum-dot spin qubit with coherence limited by charge noise
• A programmable two-qubit quantum processor in silicon
• Storing quantum information for 30 seconds in a nanoelectronic device
• Quantum CNOT Gate for Spins in Silicon
• Relaxation, dephasing, and quantum control of electron spins in double quantum dots
• Quantum simulation of a Fermi-Hubbard model using a semiconductor quantum dot array
• Scalable gate architecture for densely packed semiconductor spin qubits
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• Enhancing the Coherence of a Spin Qubit by Operating it as a Feedback Loop That Controls its Nuclear Spin Bath
• Coherent spin manipulation in an exchange-only qubit
• Noise suppression using symmetric exchange gates in spin qubits
• The Resonant Exchange Qubit
• Fast sensing of double-dot charge arrangement and spin state with an rf sensor quantum dot
• Dynamic Nuclear Polarization with Single Electron Spins
• Quantum tomography of an entangled three-spin state in silicon
• Machine learning enables completely automatic tuning of a quantum device faster than human experts
• Spectrum of the Nuclear Environment for GaAs Spin Qubits
• Closed-loop control of a GaAs-based singlet-triplet spin qubit with 99.5% gate fidelity and low leakage
• Site-selective quantum control in an isotopically enriched 28Si/SiGe quadruple quantum dot
• Relaxation and Readout Visibility of a Singlet-Triplet Qubit in an Overhauser Field Gradient
• Spectroscopy of cross-correlations of environmental noises with two qubits
• Fast spin exchange between two distant quantum dots
• Negative spin exchange in a multielectron quantum dot
• Probabilistic teleportation of a quantum dot spin qubit

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• Review of performance metrics of spin qubits in gated semiconducting nanostructures
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• Two-qubit logic between distant spins in silicon
• Universal control of four singlet-triplet qubits
• Nonlinear response and crosstalk of electrically driven silicon spin qubits
• High-fidelity two-qubit gates of hybrid superconducting-semiconducting singlet-triplet qubits
• Jellybean quantum dots in silicon for qubit coupling and on-chip quantum chemistry
• Real-time two-axis control of a spin qubit
• Autonomous estimation of high-dimensional Coulomb diamonds from sparse measurements
• Crosstalk analysis for simultaneously driven two-qubit gates in spin qubit arrays
• Stable bipolarons in open quantum systems
• Bridging the reality gap in quantum devices with physics-aware machine learning
• Machine learning optimization of Majorana hybrid nanowires
• Identifying Pauli spin blockade using deep learning
• Physics-informed tracking of qubit fluctuations
• Fast high-fidelity geometric gates for singlet-triplet qubits
• Autonomous Bootstrapping of Quantum Dot Devices
• Gate reflectometry in dense quantum dot arrays
• Probing two-qubit capacitive interactions beyond bilinear regime using dual Hamiltonian parameter estimations
• Topological gap protocol based machine learning optimization of Majorana hybrid wires
• Readout using Resonant Tunneling in Silicon Spin Qubits
• Proposal for a nonadiabatic geometric gate with an Andreev spin qubit
• Operating two exchange-only qubits in parallel
• Five and three quantum dot systems as apparatuses for measuring energy-levels
• Mitigation of exchange cross-talk in dense quantum dot arrays
• Theory on electron-phonon spin dehphasing in GaAs multi-electron double quantum dots
• Theory of the Simultaneous Transient Dispersive Readout of Multiple Spin Qubits
• Higher order spin interactions mediated by the substrate
• Model validation and error attribution for a drifting qubit
• Exploring Entanglement Spectrum and Phase Diagram in multi-electron Quantum Dot Chains