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arXiv · 1404.1712

High-Fidelity Single-Qubit Gates for Two-Electron Spin Qubits in GaAs

Pascal Cerfontaine·Tim Botzem·David P. DiVincenzo·Hendrik Bluhm
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Abstract

Single-qubit operations on singlet-triplet qubits in GaAs double quantum dots have not yet reached the fidelities required for fault-tolerant quantum information processing. Considering experimentally important constraints and using measured noise spectra, we numerically minimize the effect of decoherence (including high-frequency 1/f-like noise) and show theoretically that quantum gates with fidelities higher than 99.9% are achievable. We also present a self-consistent tuning protocol which should allow the elimination of individual systematic gate errors directly in an experiment.

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Pascal Cerfontaine, Tim Botzem, David P. DiVincenzo, Hendrik Bluhm. 2014-04-07. High-Fidelity Single-Qubit Gates for Two-Electron Spin Qubits in GaAs. https://doi.org/10.1103/physrevlett.113.150501

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