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arXiv · 2008.11176

Tensor Networks Can Resolve Fermi Surfaces

Quinten Mortier·Norbert Schuch·Frank Verstraete·Jutho Haegeman
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Abstract

We demonstrate that projected entangled-pair states (PEPS) are able to represent ground states of critical, fermionic systems exhibiting both 1d and 0d Fermi surfaces on a 2D lattice with an efficient scaling of the bond dimension. Extrapolating finite size results for the Gaussian restriction of fermionic projected entangled-pair states to the thermodynamic limit, the energy precision as a function of the bond dimension is found to improve as a power law, illustrating that an arbitrary precision can be obtained by increasing the bond dimension in a controlled manner. In this process, boundary conditions and system sizes have to be chosen carefully so that nonanalyticities of the Ansatz, rooted in its nontrivial topology, are avoided.

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Quinten Mortier, Norbert Schuch, Frank Verstraete, Jutho Haegeman. 2022-11-13. Tensor Networks Can Resolve Fermi Surfaces. https://doi.org/10.1103/physrevlett.129.206401

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