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arXiv · 1004.1975

Disorder-Induced Order in Quantum XY Chains

Armand Niederberger·Marek M. Rams·Jacek Dziarmaga·Fernando M. Cucchietti·Jan Wehr·Maciej Lewenstein
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Abstract

We observe signatures of disorder-induced order in 1D XY spin chains with an external, site-dependent uni-axial random field within the XY plane. We numerically investigate signatures of a quantum phase transition at T=0, in particular an upsurge of the magnetization in the direction orthogonal to the external magnetic field, and the scaling of the block-entropy with the amplitude of this field. Also, we discuss possible realizations of this effect in ultra-cold atom experiments.

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Armand Niederberger, Marek M. Rams, Jacek Dziarmaga, Fernando M. Cucchietti, Jan Wehr, Maciej Lewenstein. 2010-04-12. Disorder-Induced Order in Quantum XY Chains. https://doi.org/10.1103/physreva.82.013630

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