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arXiv · 2102.06715

Simulation of three-dimensional quantum systems with projected entangled-pair states

Patrick C. G. Vlaar·Philippe Corboz
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Abstract

Tensor network algorithms have proven to be very powerful tools for studying one- and two-dimensional quantum many-body systems. However, their application to three-dimensional (3D) quantum systems has so far been limited, mostly because the efficient contraction of a 3D tensor network is very challenging. In this paper we develop and benchmark two contraction approaches for infinite projected entangled-pair states (iPEPS) in 3D. The first approach is based on a contraction of a finite cluster of tensors including an effective environment to approximate the full 3D network. The second approach performs a full contraction of the network by first iteratively contracting layers of the network with a boundary iPEPS, followed by a contraction of the resulting quasi-2D network using the corner transfer matrix renormalization group. Benchmark data for the Heisenberg and Bose-Hubbard models on the cubic lattice show that the algorithms provide competitive results compared to other approaches, making iPEPS a promising tool to study challenging open problems in 3D.

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Patrick C. G. Vlaar, Philippe Corboz. 2021-02-12. Simulation of three-dimensional quantum systems with projected entangled-pair states. https://doi.org/10.1103/physrevb.103.205137

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