arXiv:1708.07539 · Physical review. B./Physical review. B

Decoherence of two coupled singlet-triplet spin qubits

Yang-Le Wu, S. Das Sarma

Published Oct 6, 2017• 9 citations

Abstract

We study a pair of capacitively coupled singlet-triplet spin qubits. We characterize the two-qubit decoherence through two complementary measures, the decay time of coupled-qubit oscillations and the fidelity of entangled state preparation. We provide a quantitative map of their dependence on charge noise and field noise, and we highlight the magnetic field gradient across each singlet-triplet qubit as an effective tool to suppress decoherence due to charge noise.

DOI: 10.1103/physrevb.96.165301

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