First- and Second-Order Phase Transitions in the d=2 XY Model

作者：Robert H. Swendsen · 发表于：Physical Review Letters · 年份：1982 · DOI：10.1103/physrevlett.49.1302 · 被引用次数：53 · 研究领域：Theoretical and Computational Physics、Material Dynamics and Properties、Advanced Thermodynamics and Statistical Mechanics

The $d=2$ $\mathrm{XY}$ model is generalized to include an operator that couples directly to the vortex core energy, while maintaining the full symmetry of the original model. In addition to the usual Kosterlitz-Thouless transition, the model exhibits a true first-order transition and a pseudo first-order transition. The excitations of the model include fractionally charged vortices. Implications for the $d=2$ melting problem are discussed.