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arXiv · 1907.10596

Reducing the complexity of finite-temperature auxiliary-field quantum Monte Carlo

C. N. Gilbreth·S. Jensen·Y. Alhassid
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Abstract

The auxiliary-field quantum Monte Carlo (AFMC) method is a powerful and widely used technique for ground-state and finite-temperature simulations of quantum many-body systems. We introduce several algorithmic improvements for finite-temperature AFMC calculations of dilute fermionic systems that reduce the computational complexity of most parts of the algorithm. This is principally achieved by reducing the number of single-particle states that contribute at each configuration of the auxiliary fields to a number that is of the order of the number of fermions. Our methods are applicable for both the canonical and grand-canonical ensembles. We demonstrate the reduced computational complexity of the methods for the homogeneous unitary Fermi gas.

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C. N. Gilbreth, S. Jensen, Y. Alhassid. 2021-03-17. Reducing the complexity of finite-temperature auxiliary-field quantum Monte Carlo. https://arxiv.org/abs/1907.10596

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