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arXiv · 0710.3289

Transient magnetotransport through a quantum wire

Vidar Gudmundsson·Gunnar Thorgilsson·Chi-Shung Tang·Valeriu Moldoveanu
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Abstract

We consider an ideal parabolic quantum wire in a perpendicular magnetic field. A simple Gaussian shaped scattering potential well or hill is flashed softly on and off with its maximum at $t=0$, mimicking a temporary broadening or narrowing of the wire. By an extension of the Lippmann-Schwinger formalism to time-dependent scattering potentials we investigate the effects on the continuous current that is driven through the quantum wire with a vanishingly small forward bias. The Lippmann-Schwinger approach to the scattering process enables us to investigate the interplay between geometrical effects and effects caused by the magnetic field.

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Vidar Gudmundsson, Gunnar Thorgilsson, Chi-Shung Tang, Valeriu Moldoveanu. 2007-10-17. Transient magnetotransport through a quantum wire. https://doi.org/10.1103/physrevb.77.035329

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