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Weakly nonlinear quantum transport: an exactly solvable model

Jian Wang·Qingrong Zheng·Hong Guo
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Abstract

We have studied the weakly non-linear quantum transport properties of a two-dimensional quantum wire which can be solved exactly. The non-linear transport coefficients have been calculated and interesting physical properties revealed. In particular we found that as the incoming electron energy approaches a resonant point given by energy $E=E_r$, where the transport is characterized by a complete reflection, the second order non-linear conductance changes its sign. This has interesting implications to the current-voltage characteristics. We have also investigated the establishment of the gauge invariance condition. We found that for systems with a finite scattering region, correction terms to the theoretical formalism are needed to preserve the gauge invariance. These corrections were derived analytically for this model.

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Jian Wang, Qingrong Zheng, Hong Guo. 1996-10-25. Weakly nonlinear quantum transport: an exactly solvable model. https://doi.org/10.1103/physrevb.55.9763

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