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arXiv · 1707.03545

Quantum coherence of planar spin models with Dzyaloshinsky-Moriya interaction

Chandrashekar Radhakrishnan·Igor Ermakov·Tim Byrnes
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Abstract

The quantum coherence of one dimensional planar spin models with the Dzyaloshinsky-Moriya interaction is investigated. The anisotropic XY model, the isotropic XX model and the transverse field model are studied in the large N-limit using the two qubit reduced density matrices and the two point correlation functions. From our investigations we find that the coherence as measured using the Jensen-Shannon divergence can be used to detect the quantum phase transitions and the quantum critical points. The derivative of coherence shows non-analytic behavior at the critical points leading to the conclusions that these transitions are of second order. Further we show that the presence of the Dzyaloshinsky-Moriya coupling suppresses the phase transition due to the residual ferromagnetism which is caused by spin canting.

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Chandrashekar Radhakrishnan, Igor Ermakov, Tim Byrnes. 2017-07-12. Quantum coherence of planar spin models with Dzyaloshinsky-Moriya interaction. https://doi.org/10.1103/physreva.96.012341

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