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arXiv · 1705.08177

Disorder-induced dephasing in backscattering-free quantum transport

Clemens Gneiting·Franco Nori
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Abstract

We analyze the disorder-perturbed transport of quantum states in the absence of backscattering. This comprises, for instance, the propagation of edge-mode wave packets in topological insulators, or the propagation of photons in inhomogeneous media. We quantify the disorder-induced dephasing, which we show to be bound. Moreover, we identify a gap condition to remain in the backscattering-free regime despite disorder-induced momentum broadening. Our analysis comprises the full disorder-averaged quantum state, on the level of both populations and coherences, appreciating states as potential carriers of quantum information. The well-definedness of states is guaranteed by our treatment of the nonequilibrium dynamics with Lindblad master equations.

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Clemens Gneiting, Franco Nori. 2017-11-01. Disorder-induced dephasing in backscattering-free quantum transport. https://doi.org/10.1103/physrevlett.119.176802

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