【摘要】 应用动力学蒙特卡罗模拟方法,对二维Ising模型和二维XY模型的aging现象展开数值研究.系统在零外场条件下从高温无序相淬火到临界温度Tc时,通过测量自关联函数A(t,t′),观察到二维Ising模型和二维XY模型的aging现象,获得更精确的动力学临界指数λc和z的值.特别是对二维XY模型,当初始态为完全无序态时,模拟结果证实存在关于标度行为的对数修正.更多还原

【Abstract】 With a large-scale Monte Carlo simulation,the aging of the two-dimensional dynamic Ising and XY models is numerically studied.Starting from a disordered state,the systems are quenched to critical temperature T_c and then evolve according to dynamics of model A.By calculating the autocorrelation function A(t,t’)we observe the aging phenomenon for both spin systems.Then,relatively accurate values of the dynamic critical exponent λ_c and z are estimated.Especially,we confirm that for the two-dimensional XY model,there is a strong logarithmic correction to scaling in the dynamic relaxation starting from a completely disordered.更多还原