Nonlinear Sigma Model for Disordered Media: Replica Trick for Non-Perturbative Results and Interactions

Igor V. Lerner

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Nonlinear Sigma Model for Disordered Media: Replica Trick for Non-Perturbative Results and Interactions

Igor V. Lerner

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Abstract

In these lectures, given at the NATO ASI at Windsor (2001), applications of the replicas nonlinear sigma model to disordered systems are reviewed. A particular attention is given to two sets of issues. First, obtaining non-perturbative results in the replica limit is discussed, using as examples (i) an oscillatory behaviour of the two-level correlation function and (ii) long-tail asymptotes of different mesoscopic distributions. Second, a new variant of the sigma model for interacting electrons in disordered normal and superconducting systems is presented, with demonstrating how to reduce it, under certain controlled approximations, to known ``phase-only'' actions, including that of the ``dirty bosons'' model.

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Igor V. Lerner. 2002-05-27. Nonlinear Sigma Model for Disordered Media: Replica Trick for Non-Perturbative Results and Interactions. https://arxiv.org/abs/cond-mat/0205555

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