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arXiv · 1312.6177

Quantum Monte Carlo measurement of the chemical potential of helium-4

C. M. Herdman·A. Rommal·A. Del Maestro
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Abstract

A path integral Monte Carlo method based on the worm algorithm has been developed to compute the chemical potential of interacting bosonic quantum fluids. By applying it to finite-sized systems of helium-4 atoms, we have confirmed that the chemical potential scales inversely with the number of particles to lowest order. The introduction of a simple scaling form allows for the extrapolation of the chemical potential to the thermodynamic limit, where we observe excellent agreement with known experimental results for helium-4 at saturated vapor pressure. We speculate on future applications of the proposed technique, including its use in studies of confined quantum fluids.

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C. M. Herdman, A. Rommal, A. Del Maestro. 2013-12-20. Quantum Monte Carlo measurement of the chemical potential of helium-4. https://doi.org/10.1103/physrevb.89.224502

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