A δ-function-like peak in the specific heat of two-dimensional vortex lattice: Monte Carlo study

A repulsive vortex-vortex interaction model was used to numerically study the melting transition of the two-dimensional vortex system with Monte Carlo method. Then a δ-function-like peak in the specific heat was observed and the internal energy showed a sharp drop at the melting temperature, which indicated that there exists a first-order melting transition at finite temperatures. The Lindemann criterion was also investigated and valid, but different from previous simulation results. Project supported by the Science and Technology Ministry of China (No. NKBRST-G19990646) and Zhejiang Provincial Natural Science Foundation (No. 199031)