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arXiv · 2502.13454

Accurate Simulation of the Hubbard Model with Finite Fermionic Projected Entangled Pair States

Wen-Yuan Liu·Huanchen Zhai·Ruojing Peng·Zheng-Cheng Gu·Garnet Kin-Lic Chan
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Abstract

We demonstrate the use of finite-size fermionic projected entangled pair states, in conjunction with variational Monte Carlo, to perform accurate simulations of the ground-state of the 2D Hubbard model. Using bond dimensions of up to $D=28$, we show that we can surpass state-of-the-art DMRG energies that use up to $m=32000$ SU(2) multiplets on 8-leg ladders. We further apply our methodology to $10\times 16$, $12\times 16$ and $16 \times 16$ lattices at $1/8$ hole doping and observe the dimensional crossover between stripe orientations. Our work shows the power of finite-size fermionic tensor networks to resolve the physics of the 2D Hubbard model and related problems.

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Wen-Yuan Liu, Huanchen Zhai, Ruojing Peng, Zheng-Cheng Gu, Garnet Kin-Lic Chan. 2025-02-19. Accurate Simulation of the Hubbard Model with Finite Fermionic Projected Entangled Pair States. https://doi.org/10.1103/r4q9-4yvj

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