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arXiv · 1812.01113

Melting of a two-dimensional monodisperse cluster crystal to a cluster liquid

Wenlong Wang·Rogelio Díaz-Méndez·Mats Wallin·Jack Lidmar·Egor Babaev
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Abstract

Monodisperse ensembles of particles that have cluster crystalline phases at low temperatures can model a number of physical systems, such as vortices in type-1.5 superconductors, colloidal suspensions and cold atoms. In this work we study a two-dimensional cluster-forming particle system interacting via an ultrasoft potential. We present a simple mean-field characterization of the cluster-crystal ground state, corroborating with Monte Carlo simulations for a wide range of densities. The efficiency of several Monte Carlo algorithms are compared and the challenges of thermal equilibrium sampling are identified. We demonstrate that the liquid to cluster-crystal phase transition is of first order and occurs in a single step, and the liquid phase is a cluster liquid.

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Wenlong Wang, Rogelio Díaz-Méndez, Mats Wallin, Jack Lidmar, Egor Babaev. 2019-04-25. Melting of a two-dimensional monodisperse cluster crystal to a cluster liquid. https://doi.org/10.1103/physreve.99.042140

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