arXiv:0905.3065

On the quantum criticality in the ground and the thermal states of XX model

Wonmin Son, Vlatko Vedral

Published May 19, 2009• 2 citations

Abstract

We compare the critical behavior of the ground state and the thermal state of the XX model. We analyze the full energy spectrum and the eigenstates to reconstruct the ground state and the thermally excited state. With the solutions, we discuss about several physical properties of the states, which are related to quantum phase transition, in various limits, at zero temperature as well as at a thermal equilibrium.

DOI: 10.48550/arxiv.0905.3065

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