二维完全阻挫$lt;i$gt;XY$lt;/i$gt;模型的动力学指数

采用大规模动力学蒙特卡罗模拟方法，对二维完全阻挫XY模型的Kosterlitz-Thouless（KT）型相变展开数值研究.系统从有序初始态出发演化到高于KT相变的温度，以普适的动力学标度形式为基础，通过测量磁化和Binder累积量，得出动力学关联时间和平衡态空间关联长度，确定出更精确的动力学指数z.特别是建议并证实了一种在KT相变温度以上（T>T_KT），独立判断动力学指数z的方法.模拟结果表明，动力学指数z≈2，这与在相变温度以下（T<T_KT）测量的结果一致.关键词：蒙特卡罗法动力学指数Kosterlitz-Thouless相变XY模型')" href="#">二维完全阻挫XY模型

The dynamic exponent of two-dimensional fully frustrated XY model

With a large-scale Monte Carlo simulation, non-equilibrium dynamics of the two-dimensional fully frustrated XY model is investigated. We tackle the Kosterlitz-Thouless phase transition. Starting from an ordered initial state, we study the dynamic evolution of the magnetization as well as a specifically defined Binder cumulant. From the dynamic scaling ansatz, we extract the correlating time of the dynamics and the spatial correlation length of the equilibrium state. The dynamic exponent z is determined with relatively high accuracy. Especially, we suggest and demonstrate how one may directly measure the dynamic exponent z above T_KT from the scaling fit of the Binder cumulant. These results indicate that the dynamic exponent z fluctuates around z=2, and this is consistent with that observed at temperatures below the transition temperature T_KT.