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arXiv · 0903.3491

Time-dependent transport via the generalized master equation through a finite quantum wire with an embedded subsystem

Vidar Gudmundsson·Cosmin Gainar·Chi-Shung Tang·Valeriu Moldoveanu·Andrei Manolescu
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Abstract

The authors apply the generalized master equation to analyze time-dependent transport through a finite quantum wire with an embedded subsystem. The parabolic quantum wire and the leads with several subbands are described by a continuous model. We use an approach originally developed for a tight-binding description selecting the relevant states for transport around the bias-window defined around the values of the chemical potential in the left and right leads in order to capture the effects of the nontrivial geometry of the system in the transport. We observe a partial current reflection as a manifestation of a quasi-bound state in an embedded well and the formation of a resonance state between an off-set potential hill and the boundary of the system.

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Vidar Gudmundsson, Cosmin Gainar, Chi-Shung Tang, Valeriu Moldoveanu, Andrei Manolescu. 2009-10-28. Time-dependent transport via the generalized master equation through a finite quantum wire with an embedded subsystem. https://doi.org/10.1088/1367-2630%2F11%2F11%2F113007

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