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Bosonization for disordered and chaotic systems

K. B. Efetov·G. Schwiete·K. Takahashi
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Abstract

Using a supersymmetry formalism, we reduce exactly the problem of electron motion in an external potential to a new supermatrix model valid at all distances. All approximate nonlinear sigma models obtained previously for disordered systems can be derived from our exact model using a coarse-graining procedure. As an example, we consider a model for a smooth disorder and demonstrate that using our approach does not lead to a 'mode-locking' problem. As a new application, we consider scattering on strong impurities for which the Born approximation cannot be used. Our method provides a new calculational scheme for disordered and chaotic systems.

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K. B. Efetov, G. Schwiete, K. Takahashi. 2004-01-17. Bosonization for disordered and chaotic systems. https://doi.org/10.1103/physrevlett.92.026807

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