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arXiv · 0905.0877

O(N) symmetry-breaking quantum quench: Topological defects versus quasiparticles

Michael Uhlmann·Ralf Schützhold·Uwe R. Fischer
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Abstract

We present an analytical derivation of the winding number counting topological defects created by an O(N) symmetry-breaking quantum quench in N spatial dimensions. Our approach is universal in the sense that we do not employ any approximations apart from the large-$N$ limit. The final result is nonperturbative in N, i.e., it cannot be obtained by %the usual an expansion in 1/N, and we obtain far less topological defects than quasiparticle excitations, in sharp distinction to previous, low-dimensional investigations.

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Michael Uhlmann, Ralf Schützhold, Uwe R. Fischer. 2009-05-06. O(N) symmetry-breaking quantum quench: Topological defects versus quasiparticles. https://doi.org/10.1103/physrevd.81.025017

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