Reentrant Melting in Laser Field Modulated Colloidal Suspensions

We present results from a Monte Carlo simulation study of the phase diagram and the order of the modulated liquid to crystal transition in laser field modulated colloids. We find that for low values of $\beta V_e$, the strength of the modulation potential, the transition is first order, but changes to a continuous transition for high values of $\beta V_e$, in agreement with the conclusions from the density functional theory of laser induced freezing. However, we find in the simulation a novel reentrant laser induced melting transition from the crystal to the modulated liquid phase with increasing $\beta V_e$, unlike the (mean field) density functional phase diagram.