Hysteresis and reentrant melting of a self-organized system of classical particles confined in a parabolic trap

Abstract

The melting of a self-organized system composed of classical particles confined in a two-dimensional parabolic trap and interacting through a potential with a short-range attractive part and a long-range repulsive potential is studied. Different behaviors of the melting temperature are found depending on the strength 共B兲 of the attractive part of the interparticle potential. The melting of a system consisting of small bubbles takes place through a two-step melting process. A reentrant behavior and a thermally induced structural phase transition are observed in a small region of the 共B , ␬ 兲 space. A hysteresis effect in the configuration of the particles is observed as a function of temperature. This is a consequence of the presence of a potential barrier between different configurations of the system.