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arXiv · 2201.01296

Dynamical tuning of the chemical potential to achieve a target particle number in grand canonical Monte Carlo simulations

Cole Miles·Benjamin Cohen-Stead·Owen Bradley·Steven Johnston·Richard Scalettar·Kipton Barros
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Abstract

We present a method to facilitate Monte Carlo simulations in the grand canonical ensemble given a target mean particle number. The method imposes a fictitious dynamics on the chemical potential, to be run concurrently with the Monte Carlo sampling of the physical system. Corrections to the chemical potential are made according to time-averaged estimates of the mean and variance of the particle number, with the latter being proportional to thermodynamic compressibility. We perform a variety of tests, and in all cases find rapid convergence of the chemical potential -- inexactness of the tuning algorithm contributes only a minor part of the total measurement error for realistic simulations.

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Cole Miles, Benjamin Cohen-Stead, Owen Bradley, Steven Johnston, Richard Scalettar, Kipton Barros. 2022-01-04. Dynamical tuning of the chemical potential to achieve a target particle number in grand canonical Monte Carlo simulations. https://doi.org/10.1103/physreve.105.045311

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