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arXiv · 2305.02091

Finite-Entanglement Scaling of 2D Metals

Quinten Mortier·Ming-Hao Li·Jutho Haegeman·Nick Bultinck
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Abstract

We extend the study of finite-entanglement scaling from one-dimensional gapless models to two-dimensional systems with a Fermi surface. In particular, we show that the entanglement entropy of a contractible spatial region with linear size $L$ scales as $S\sim L\log[\xi f(L/\xi)]$ in the optimal tensor network, and hence area-law entangled, state approximation to a metallic state, where $f(x)$ is a scaling function which depends on the shape of the Fermi surface and $\xi$ is a finite correlation length induced by the restricted entanglement. Crucially, the scaling regime can be realized with numerically tractable bond dimensions. We also discuss the implications of the Lieb-Schultz-Mattis theorem at fractional filling for tensor network state approximations of metallic states.

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Quinten Mortier, Ming-Hao Li, Jutho Haegeman, Nick Bultinck. 2023-05-03. Finite-Entanglement Scaling of 2D Metals. https://doi.org/10.1103/physrevlett.131.266202

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