Effects of random fields on the dynamics of the one-dimensional quantum XXZ model

Yin-Yang Shen; Xiao-Juan Yuan; Xiang-Mu Kong

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arXiv · 1010.4348

Effects of random fields on the dynamics of the one-dimensional quantum XXZ model

Yin-Yang Shen·Xiao-Juan Yuan·Xiang-Mu Kong

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Abstract

The dynamics of the one-dimensional spin-1/2 quantum XXZ model with random fields is investigated by the recurrence relations method. When the fields satisfy the bimodal distribution, the system shows a crossover between a collective-mode behavior and a central-peak one with increasing field while the anisotropy parameter Δ is small; a disordered behavior replaces the crossover as Δ increases. For the cases of Gaussian and double-Gaussian distributions, when the standard deviation is small, the results are similar to that of the bimodal distribution; while the standard deviation is large enough, the system only shows a disordered behavior regardless of Δ.

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Yin-Yang Shen, Xiao-Juan Yuan, Xiang-Mu Kong. 2011-05-10. Effects of random fields on the dynamics of the one-dimensional quantum XXZ model. https://arxiv.org/abs/1010.4348

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