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arXiv · 2308.12005

Delay Update in determinant quantum Monte Carlo

Fanjie Sun·Xiao Yan Xu
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Abstract

Determinant quantum Monte Carlo (DQMC) is a widely used unbiased numerical method for simulating strongly correlated electron systems. However, the update process in DQMC is often a bottleneck for its efficiency. To address this issue, we propose a generalized delay update scheme that can handle both onsite and extended interactions. Our delay update scheme can be implemented in both zero-temperature and finite-temperature versions of DQMC. We apply the delay update scheme to various strongly correlated electron models and evaluate its efficiency under different conditions. Our results demonstrate that the proposed delay update scheme significantly improves the efficiency of DQMC simulations, enable it to simulate larger system size.

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Fanjie Sun, Xiao Yan Xu. 2023-08-23. Delay Update in determinant quantum Monte Carlo. https://doi.org/10.1103/physrevb.109.235140

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