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arXiv · 2007.05977

Freezing and re-entrant melting of hard discs in a one-dimensional potential:\\ Predictions based on a pressure-balance equation

Alexander Kraft·Sabine H. L. Klapp
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Abstract

We investigate theoretically the freezing behaviour of a two-dimensional (2D) system of hard discs on a one-dimensional (1D) external potential (typically called laser-induced freezing). As shown by earlier theoretical and numerical studies, one observes freezing of the modulated liquid upon increase of the substrate potential amplitude, and re-entrant melting back into the modulated liquid when the substrate potential amplitude is increased even further. The purpose of our present work is to calculate the freezing and re-entrant melting phase diagram based on information from the bulk system. To this end, we employ an integrated pressure-balance equation derived from density functional theory [Phys. Rev. E \textbf{101}, 012609 (2020)]. Furthermore, we define a measure to quantify the influence of registration effects that qualitatively explain re-entrant melting. Despite severe approximations, the calculated phase diagram shows good agreement with the known phase diagram obtained by Monte Carlo simulations.

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Alexander Kraft, Sabine H. L. Klapp. 2020-07-12. Freezing and re-entrant melting of hard discs in a one-dimensional potential:\\ Predictions based on a pressure-balance equation. https://doi.org/10.1103/physreve.102.022606

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