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Chinese Physics Letters

Decay of Loschmidt Echo at a Critical Point in the Lipkin–Meshkov–Glick model

Ping Wang, Qiang Zheng, Wen-ge Wang

Published Aug 1, 2010• 6 citations
Publisher

Abstract

An analytical expression of the Loschmidt echo in the Lipkin–Meshkov–Glick model is derived in the thermodynamical limit. It is used in the study of the decaying behaviour of the echo at the critical point of a quantum phase transition of the model. It is shown that the echo has a power law decay for relatively long times.
DOI
10.1088/0256-307x/27/8/080301

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