Boundary-law scaling of entanglement entropy in diffusive metals

Andrew C. Potter

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arXiv · 1408.1094

Boundary-law scaling of entanglement entropy in diffusive metals

Andrew C. Potter

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Abstract

Entanglement structure serves as a powerful way to characterize quantum many-body phases. This is particularly so for gapless quantum liquids, where entanglement-based tools provide one of the only means to systematically characterize these complicated phases. For example, the Fermi-surface structure of Fermi-liquids is revealed in entanglement entropy by a log-correction to the typical boundary-law scaling of simpler quantum ground-states. In this paper, I analyze the entanglement structure of a disordered, but delocalized diffusive metal. Using a combination of analytic arguments and numerical calculations, I show that, despite having the same number of extended gapless excitations as a clean Fermi-liquid, the diffusive metal exhibits only boundary-law entanglement scaling. This result pinpoints the sharp Fermi-surface structure, rather than the finite density of gapless excitations, as the origin of the log-correction in the Fermi-liquid entanglement scaling.

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Andrew C. Potter. 2014-08-05. Boundary-law scaling of entanglement entropy in diffusive metals. https://arxiv.org/abs/1408.1094

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