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arXiv · 1508.07187

Incoherent ensemble dynamics in disordered systems

Clemens Gneiting·Felix R. Anger·Andreas Buchleitner
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Abstract

We derive a quantum master equation which describes the dynamics of the ensemble-averaged state of homogeneous disorder models at short times, and mediates a transition from coherent superpositions into classical mixtures. While each single realization follows unitary dynamics, this decoherencelike behavior arises as a consequence of the ensemble average. The master equation manifestly reflects the translational invariance of the disorder correlations and allows us to relate the disorder-induced dynamics to a collisional decoherence process, where the disorder correlations determine the spatial decay of coherences. We apply our theory to the (one-dimensional) Anderson model.

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Clemens Gneiting, Felix R. Anger, Andreas Buchleitner. 2016-04-06. Incoherent ensemble dynamics in disordered systems. https://doi.org/10.1103/physreva.93.032139

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