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arXiv · 0908.1986

Criticality and entanglement in random quantum systems

Gil Refael·Joel E. Moore
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Abstract

We review studies of entanglement entropy in systems with quenched randomness, concentrating on universal behavior at strongly random quantum critical points. The disorder-averaged entanglement entropy provides insight into the quantum criticality of these systems and an understanding of their relationship to non-random ("pure") quantum criticality. The entanglement near many such critical points in one dimension shows a logarithmic divergence in subsystem size, similar to that in the pure case but with a different universal coefficient. Such universal coefficients are examples of universal critical amplitudes in a random system. Possible measurements are reviewed along with the one-particle entanglement scaling at certain Anderson localization transitions. We also comment briefly on higher dimensions and challenges for the future.

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Gil Refael, Joel E. Moore. 2009-08-13. Criticality and entanglement in random quantum systems. https://doi.org/10.1088/1751-8113%2F42%2F50%2F504010

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