Laser-induced melting in two-dimensional colloidal systems

The dynamics of a charged two-dimensional colloidal system in the presence of a one-dimensionally modulated laser field is studied by using Brownian dynamics simulations. The present model consists of interacting point particles in two dimensions, including effects of screened Coulomb force, laser-induced periodic force, Stokes drag force, and thermal noise. In the case of low particle density and the laser potential periodicity commensurate with the mean interparticle distance, computer simulation results find four characteristic phases with three crossovers as a function of the laser field strength.