Decoherence of two coupled singlet-triplet spin qubits

Yang-Le Wu; S. Das Sarma

doi:10.1103/physrevb.96.165301

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arXiv · 1708.07539

Decoherence of two coupled singlet-triplet spin qubits

Yang-Le Wu·S. Das Sarma

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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.

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Yang-Le Wu, S. Das Sarma. 2017-10-08. Decoherence of two coupled singlet-triplet spin qubits. https://doi.org/10.1103/physrevb.96.165301

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