Resonantly Driven Singlet-Triplet Spin Qubit in Silicon.

  title={Resonantly Driven Singlet-Triplet Spin Qubit in Silicon.},
  author={Kenta Takeda and Akito Noiri and Jun Yoneda and Takashi Nakajima and Seigo Tarucha},
  journal={Physical review letters},
  volume={124 11},
We report implementation of a resonantly driven singlet-triplet spin qubit in silicon. The qubit is defined by the two-electron antiparallel 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  μs that is limited by dephasing due to the ^{29}Si nuclei rather than charge noise thanks to the symmetric operation and a large micromagnet Zeeman field gradient. The randomized… 

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