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arXiv · 1910.06814

An efficient method for grand-canonical twist averaging in quantum Monte Carlo calculations

Sam Azadi·W. M. C. Foulkes
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Abstract

We introduce a simple but efficient method for grand-canonical twist averaging in quantum Monte Carlo calculations. By evaluating the thermodynamic grand potential instead of the ground state total energy, we greatly reduce the sampling errors caused by twist-dependent fluctuations in the particle number. We apply this method to the electron gas and to metallic lithium, aluminum, and solid atomic hydrogen. We show that, even when using a small number of twists, grand-canonical twist averaging of the grand potential produces better estimates of ground state energies than the widely used canonical twist-averaging approach.

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Sam Azadi, W. M. C. Foulkes. 2019-10-15. An efficient method for grand-canonical twist averaging in quantum Monte Carlo calculations. https://doi.org/10.1103/physrevb.100.245142

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