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arXiv · 1008.3089

Quantum Coherence in a One-Electron Semiconductor Charge Qubit

K. D. Petersson·J. R. Petta·H. Lu·A. C. Gossard
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Abstract

We study quantum coherence in a semiconductor charge qubit formed from a GaAs double quantum dot containing a single electron. Voltage pulses are applied to depletion gates to drive qubit rotations and non-invasive state readout is achieved using a quantum point contact charge detector. We measure a maximum coherence time of ~7 ns at the charge degeneracy point, where the qubit level splitting is first-order-insensitive to gate voltage fluctuations. We compare measurements of the coherence time as a function of detuning with predictions from a 1/f noise model.

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K. D. Petersson, J. R. Petta, H. Lu, A. C. Gossard. 2011-05-07. Quantum Coherence in a One-Electron Semiconductor Charge Qubit. https://doi.org/10.1103/physrevlett.105.246804

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