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arXiv · 1709.04206

Wigner-function formalism applied to semiconductor quantum devices: Need for nonlocal scattering models

Rita Claudia Iotti·Fabrizio Dolcini·Fausto Rossi
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Abstract

In designing and optimizing new-generation nanomaterials and related quantum devices, dissipation versus decoherence phenomena are often accounted for via local scattering models, such as relaxation-time and Boltzmann-like schemes. Here we show that the use of such local scattering approaches within the Wigner-function formalism may lead to unphysical results, namely anomalous suppression of intersubband relaxation, incorrect thermalization dynamics, and violation of probability-density positivity. Furthermore, we propose a quantum-mechanical generalization of relaxation-time and Boltzmann-like models, resulting in nonlocal scattering superoperators that enable one to overcome such limitations.

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Rita Claudia Iotti, Fabrizio Dolcini, Fausto Rossi. 2017-09-13. Wigner-function formalism applied to semiconductor quantum devices: Need for nonlocal scattering models. https://doi.org/10.1103/physrevb.96.115420

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