Eur. Phys. J. B 83, 499-505 (2011)
https://doi.org/10.1140/epjb/e2011-20595-9

Regular Article

Melting properties of two-dimensional multi-species colloidal systems in a parabolic trap

¹ College of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, P.R. China
² Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
³ Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceará, Brazil
⁴ Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China

^a e-mail: wyangtyust@hotmail.com

Received: 20 July 2011
Received in final form: 18 September 2011
Published online: 19 October 2011

Abstract

The angular and radial melting properties of two-dimensional classical systems consisting of different types of particles confined in a parabolic trap are studied through modified Monte Carlo simulations. A universal behavior of the angular melting process is found, which occurs in multiple steps due to shell depended melting temperatures. The melting sequence of the different shells is determined by two major factors: (1) the confinement strength which each shell is subjected to, and (2) the specific structure of each shell. Further, a continuous radial disordering of the particle types forming a single circular shell is found and analyzed. This phenomenon has never been observed before in two-dimensional mono-dispersive systems. This continuous radial disordering results from the high energy barrier between different particle types in multi-species systems.