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arXiv · 1711.06338

Entanglement contour perspective for strong area law violation in a disordered long-range hopping model

Nilanjan Roy·Auditya Sharma
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Abstract

We numerically investigate the link between the delocalization-localization transition and entanglement in a disordered long-range hopping model of spinless fermions by studying various static and dynamical quantities. This includes the inverse participation ratio, level-statistics, entanglement entropy and number fluctuations in the subsystem along with quench and wave-packet dynamics. Finite systems show delocalized, quasi-localized and localized phases. The delocalized phase shows strong area-law violation whereas the (quasi)localized phase adheres to (for large subsystems) the strict area law. The idea of `entanglement contour' nicely explains the violation of area-law and its relationship with `fluctuation contour' reveals a signature at the transition point. The relationship between entanglement entropy and number fluctuations in the subsystem also carries signatures for the transition in the model. Results from Aubry-Andre-Harper model are compared in this context. The propagation of charge and entanglement are contrasted by studying quench and wavepacket dynamics at the single-particle and many-particle levels.

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Nilanjan Roy, Auditya Sharma. 2018-02-06. Entanglement contour perspective for strong area law violation in a disordered long-range hopping model. https://doi.org/10.1103/physrevb.97.125116

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