arXiv 1503.047702015-03-16quant-phcond-mat.dis-nncond-mat.str-el

Enhancement of Quantum Correlation Length in Quenched Disordered Spin Chains

Debasis Sadhukhan, Sudipto Singha Roy, Debraj Rakshit, R. Prabhu, Aditi Sen De, Ujjwal Sen

备注：: 10 pages, 7 figures
发表信息：: Phys. Rev. E 93, 012131 (2016)
DOI：: 10.1103/PhysRevE.93.012131

英文摘要：

Classical correlations of ground states typically decay exponentially and polynomially, respectively for gapped and gapless short-ranged quantum spin systems. In such systems, entanglement decays exponentially even at the quantum critical points. However, quantum discord, an information-theoretic quantum correlation measure, survives long lattice distances. We investigate the effects of quenched disorder on quantum correlation lengths of quenched averaged entanglement and quantum discord, in the anisotropic XY and XYZ spin glass and random field chains. We find that there is virtually neither reduction nor enhancement in entanglement length while quantum discord length increases significantly with the introduction of the quenched disorder.

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