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arXiv · 2101.00226

Quantum Quench dynamics in XY spin chain with ferromagnetic and antiferromagnetic interactions

Abstract

In this manuscript we investigate the one-dimensional anisotropic XY model with ferromagnetic and antiferromagnetic interactions, which gives more interesting phase diagrams and dynamic critical behaviors. By using quantum renormalization-group method, we find that there are three phases in the system: antiferromagnetic Ising phase ordered in "x direction", spin-fluid phase and ferromagnetic Ising phase ordered in "y direction". In order to study the dynamical critical behaviors of the system, two quantum quenching methods are used. In both cases, the concurrence, a measure of entanglement, oscillates periodically over time. We show that the periods are the same and can be used as a new order parameter for quantum phase transitions. For further discussion, we derive the scaling exponent, θ, and correlation length exponent, ν, from the scaling behavior of the evolution period.

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Zhe Wang, Pan-Pan Fang, Yu-Liang Xu, Chun-Yang Wang, Rong-Tao Zhang, Han Zhang, Xiang-Mu Kong. 2021-01-07. Quantum Quench dynamics in XY spin chain with ferromagnetic and antiferromagnetic interactions. https://doi.org/10.1016/j.physa.2021.126205

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