Quantum phase transition in the anisotropic one-dimensional XY model with long-range interactions

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:322

Article

Pires, A. S. T.

关键词: XY model;    Quantum phase transition;    Long range interaction;   

DOI  :  10.1016/j.jmmm.2010.01.025

来源: Elsevier

【 摘 要 】

In this paper we study the one-dimensional XY model with single ion anisotropy and long-range interaction that decay as a power law. The model has a quantum phase transition, at zero temperature, at a critical value D(c) of the anisotropy parameter D. For values of D below D(c) we use a self-consistent harmonic approximation. We have found that the critical temperature increases with D for small values of this parameter. For values of D above D(c) we use the bond operator technique and calculate the gap as a function of D, at zero temperature. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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