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arXiv · 1404.2146

Quantum transport with strong scattering: Beyond the nonlinear sigma model

K. Ziegler
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Abstract

Transport properties of a two-band system with spectral nodes are studied in the presence of random scattering. Starting from a Grassmann functional integral, we derive a bosonic representation that is based on random phase fluctuations. Averaging leads to a graphical representation of the correlation function with entangled random walks and 4-vertices. In the strong scattering limit we derive a complex transition amplitude. For the example of two-dimensional Dirac fermions we obtain a localization length proportional to the inverse scattering rate.

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K. Ziegler. 2014-04-08. Quantum transport with strong scattering: Beyond the nonlinear sigma model. https://doi.org/10.1088/1751-8113/48/5/055102

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