论文标题
2D超流体中涡流的波动的库仑气和规则
Coulomb gas sum rules for vortex-pair fluctuations in 2D superfluids
论文作者
论文摘要
使用2D XY模型的模拟表征了临界Kosterlitz-thouless（KT）过渡温度上方和下方的涡流波动。在给定温度下，在半径$ r $的圆圈中，净绕组数的涡流数量是$ r $的函数。在所有高于$ t_ {kt} $以下的所有温度下，平均平方绕组数随圆的周长而变化，并且带有$ r $的坡度在特定的热峰附近显示出一个尖锐的峰，然后在无限温度下降低到dhar与早期理论一致的无限温度下的值。我们还计算了涡旋 - 涡流分布函数，在所有温度下发现涡旋分离距离的渐近幂律变化。结合周长波动上的库仑气和规则，这些规则可用于成功模拟$ t_ {kt} $以下区域中周边斜坡峰的开始。
Vortex fluctuations above and below the critical Kosterlitz-Thouless (KT) transition temperature are characterized using simulations of the 2D XY model. The net winding number of vortices at a given temperature in a circle of radius $R$ is computed as a function of $R$. The average squared winding number is found to vary linearly with the perimeter of the circle at all temperatures above and below $T_{KT}$, and the slope with $R$ displays a sharp peak near the specific heat peak, decreasing then to a value at infinite temperature that is in agreement with an early theory by Dhar. We have also computed the vortex-vortex distribution functions, finding an asymptotic power-law variation in the vortex separation distance at all temperatures. In conjunction with a Coulomb-gas sum rule on the perimeter fluctuations, these can be used to successfully model the start of the perimeter-slope peak in the region below $T_{KT}$.
