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arXiv · 1210.4028

Semi-classical theory for quantum quenches in the O(3) non-linear sigma model

Stefano Evangelisti
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Abstract

We use the semi-classical approach to study the non-equilibrium dynamics of the O(3) non-linear sigma model. For a class of quenches defined in the text, we obtain the order parameter dynamical correlator in the thermodynamic limit. In particular we predict quench-dependent relaxation times and correlation lengths. The approach developed for the O(3) non-linear sigma model can also be applied to the transverse field Ising chain, where the semi-classical results can be directly compared to both the exact and the numerical ones, revealing the limits of the method.

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Stefano Evangelisti. 2013-01-19. Semi-classical theory for quantum quenches in the O(3) non-linear sigma model. https://doi.org/10.1088/1742-5468%2F2013%2F04%2Fp04003

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