A Path Integral Approach to Effective Non-Linear Medium

Marc Barthelemy; Henri Orland

doi:10.1007/s100510050581

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arXiv · cond-mat/9806302

A Path Integral Approach to Effective Non-Linear Medium

Marc Barthelemy·Henri Orland

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Abstract

In this article, we propose a new method to compute the effective properties of non-linear disordered media. We use the fact that the effective constants can be defined through the minimum of an energy functional. We express this minimum in terms of a path integral allowing us to use many-body techniques. We obtain the perturbation expansion of the effective constants to second order in disorder, for any kind of non-linearity. We apply our method to both cases of strong and weak non-linearities. Our results are in agreement with previous ones, and could be easily extended to other types of non-linear problems in disordered systems.

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Marc Barthelemy, Henri Orland. 1998-06-25. A Path Integral Approach to Effective Non-Linear Medium. https://doi.org/10.1007/s100510050581

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