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arXiv · 1910.00771

Resonantly driven singlet-triplet spin qubit in silicon

Kenta Takeda·Akito Noiri·Jun Yoneda·Takashi Nakajima·Seigo Tarucha
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Abstract

We report implementation of a resonantly driven singlet-triplet spin qubit in silicon. The qubit is defined by the two-electron anti-parallel spin states and universal quantum control is provided through a resonant drive of the exchange interaction at the qubit frequency. The qubit exhibits long $T_2^*$ exceeding 1 $μ$s that is limited by dephasing due to the $^{29}$Si nuclei rather than charge noise thanks to the symmetric operation and a large micro-magnet Zeeman field gradient. The randomized benchmarking shows 99.6 % single gate fidelity which is the highest reported for singlet-triplet qubits.

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Kenta Takeda, Akito Noiri, Jun Yoneda, Takashi Nakajima, Seigo Tarucha. 2019-10-02. Resonantly driven singlet-triplet spin qubit in silicon. https://doi.org/10.1103/physrevlett.124.117701

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