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arXiv · 0709.1381

Towards a dephasing diode: asymmetric and geometric dephasing

Robert S. Whitney·Alexander Shnirman·Yuval Gefen
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Abstract

We study the effect of a noisy environment on spin and charge transport in ballistic quantum wires with spin-orbit coupling (Rashba coupling). We find that the wire then acts as a ``dephasing diode'', inducing very different dephasing of the spins of right and left movers. We also show how Berry phase (geometric phase) in a curved wire can induce such asymmetric dephasing, in addition to purely geometric dephasing. We propose ways to measure these effects through spin detectors, spin-echo techniques, and Aharanov-Bohm interferometry.

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Robert S. Whitney, Alexander Shnirman, Yuval Gefen. 2008-03-26. Towards a dephasing diode: asymmetric and geometric dephasing. https://doi.org/10.1103/physrevlett.100.126806

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