MONTE-CARLO SIMULATION OF 2-DIMENSIONAL FLUX-LINE-LATTICE MELTING

A Monte Carlo simulation of a two-dimensional flux-line-lattice (FLL) melting transition is presented. The internal energy, specific beat, A brikosov ratio, and diffraction pattern of the magnitude \psi(x)\2 of the order-parameter field are calculated. By examining in detail the h ysteresis, histogram, and relaxation profiles of the internal energy, the existence of a first-order phase transition is concluded. Below th e transition temperature t(m) the diffraction pattern has six sharp pe aks corresponding to the hexagonal symmetry of the triangular FLL, whi le it shows liquidlike behavior above t(m). The sample-size dependence of the peak height clearly shows that the phase transition is the mel ting of the FLL. Comparison with earlier works is also made.