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arXiv · 2609.20020

Corner entanglement scaling with projected entangled pair states

Chloé Van Bastelaere·Rui-Zhen Huang·Laurens Vanderstraeten
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Abstract

Entanglement scaling provides a powerful probe of universal properties at quantum critical points. In two dimensions, contributions originating from a corner-shaped bipartition exhibit a universal scaling, which is determined by the underlying conformal field theory. We develop a method to extract this corner entanglement entropy from projected entangled pair states directly in the thermodynamic limit. When applied to models at a quantum critical point, we show that the corner contribution exhibits scaling with the effective correlation length, in agreement with the hypothesis of finite-entanglement scaling. Our results for the corner coefficients are consistent with other methods, demonstrating the efficiency of our method for diagnosing strongly-correlated quantum critical points in two dimensions.

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Chloé Van Bastelaere, Rui-Zhen Huang, Laurens Vanderstraeten. 2026-09-17. Corner entanglement scaling with projected entangled pair states. https://arxiv.org/abs/2609.20020

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