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arXiv · 0902.0227

Rapid Single-Shot Measurement of a Singlet-Triplet Qubit

C. Barthel·D. J. Reilly·C. M. Marcus·M. P. Hanson·A. C. Gossard
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Abstract

We report repeated single-shot measurements of the two-electron spin state in a GaAs double quantum dot. The readout scheme allows measurement with fidelity above 90% with a 7 microsecond cycle time. Hyperfine-induced precession between singlet and triplet states of the two-electron system are directly observed, as nuclear Overhauser fields are quasi-static on the time scale of the measurement cycle. Repeated measurements on millisecond to second time scales reveal evolution of the nuclear environment.

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C. Barthel, D. J. Reilly, C. M. Marcus, M. P. Hanson, A. C. Gossard. 2009-02-02. Rapid Single-Shot Measurement of a Singlet-Triplet Qubit. https://doi.org/10.1103/physrevlett.103.160503

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