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Disorder Induced Quantum Phase Transition in Random-Exchange Spin-1/2 Chains

K. Hamacher·J. Stolze·W. Wenzel
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Abstract

We investigate the effect of quenched bond-disorder on the anisotropic spin-1/2 (XXZ) chain as a model for disorder induced quantum phase transitions. We find non-universal behavior of the average correlation functions for weak disorder, followed by a quantum phase transition into a strongly disordered phase with only short-range xy-correlations. We find no evidence for the universal strong-disorder fixed point predicted by the real-space renormalization group, suggesting a qualitatively different view of the relationship between quantum fluctuations and disorder.

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K. Hamacher, J. Stolze, W. Wenzel. 2001-11-02. Disorder Induced Quantum Phase Transition in Random-Exchange Spin-1/2 Chains. https://doi.org/10.1103/physrevlett.89.127202

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