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arXiv:1512.08832 · Physical Review Letters

Quantum Dephasing in a Gated GaAs Triple Quantum Dot due to Nonergodic Noise

Matthieu R. Delbecq, Takashi Nakajima, Peter Stano, Tomohiro Otsuka, S. Amaha, Jun Yoneda, Kenta Takeda, Giles Allison, Arne Ludwig, Andreas Dirk Wieck, Seigo Tarucha

Published Jan 26, 2016• 60 citations
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Abstract

We extract the phase coherence of a qubit defined by singlet and triplet electronic states in a gated GaAs triple quantum dot, measuring on time scales much shorter than the decorrelation time of the environmental noise. In this nonergodic regime, we observe that the coherence is boosted and several dephasing times emerge, depending on how the phase stability is extracted. We elucidate their mutual relations, and demonstrate that they reflect the noise short-time dynamics.

DOI
10.1103/physrevlett.116.046802

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