Eur. Phys. J. B (2016) 89: 144
https://doi.org/10.1140/epjb/e2016-70042-6

Regular Article

Finite-temperature scaling of quantum coherence near criticality in a spin chain

¹ Institute of Signal Processing and Transmission, Nanjing University of Posts and Telecommunication, Nanjing 210003, P.R. China
² Department of Physics, Hubei Normal University, Huangshi 435002, P.R. China

^a e-mail: wwcheng@njupt.edu.cn

Received: 30 November 2015
Received in final form: 19 January 2016
Published online: 6 June 2016

Abstract

We explore quantum coherence, inherited from Wigner-Yanase skew information, to analyze quantum criticality in the anisotropic XY chain model at finite temperature. Based on the exact solutions of the Hamiltonian, the quantum coherence contained in a nearest-neighbor spin pairs reduced density matrix ρ is obtained. The first-order derivative of the quantum coherence is non-analytic around the critical point at sufficient low temperature. The finite-temperature scaling behavior and the universality are verified numerically. In particular, the quantum coherence can also detect the factorization transition in such a model at sufficient low temperature. We also show that quantum coherence contained in distant spin pairs can characterize quantum criticality and factorization phenomena at finite temperature. Our results imply that quantum coherence can serve as an efficient indicator of quantum criticality in such a model and shed considerable light on the relationships between quantum phase transitions and quantum information theory at finite temperature.