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arXiv · 1705.10937

Quantum phase transitions of a generalized compass chain with staggered Dzyaloshinskii-Moriya interaction

Qing-Qiu Wu·Wei-Hai Ni·Wen-Long You
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Abstract

We consider a class of one-dimensional compass models with staggered Dzyaloshinskii-Moriya exchange interactions in an external transverse magnetic field. Based on the exact solution derived from Jordan-Wigner approach, we study the excitation gap, energy spectra, spin correlations and critical properties at phase transitions. We explore mutual effects of the staggered Dzyaloshinskii-Moriya interaction and the magnetic field on the energy spectra and the ground-state phase diagram. Thermodynamic quantities including the entropy and the specific heat are discussed, and their universal scalings at low temperature are demonstrated.

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Qing-Qiu Wu, Wei-Hai Ni, Wen-Long You. 2017-05-31. Quantum phase transitions of a generalized compass chain with staggered Dzyaloshinskii-Moriya interaction. https://doi.org/10.1088/1361-648x%2Faa6e6d

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