随机序列展开量子蒙特卡洛模拟中非对角关联函数的测量  

Measuring off-diagonal correlation function in stochastic series expansion quantum Monte Carlo simulation

作　　者：朱文静 郭文安[1] ZHU Wenjing;GUO Wen’an(Department of Physics,Beijing Normal University,100875,Beijing,China)

机构地区：[1]北京师范大学物理学系,北京100875

出　　处：《北京师范大学学报（自然科学版）》2021年第5期593-600,共8页Journal of Beijing Normal University(Natural Science)

基　　金：国家自然科学基金资助项目(11775021,11734002)。

摘　　要：主要介绍了在随机序列展开方法中利用圈更新计算非对角关联函数的算法.以一维海森堡模型和易面XXZ模型为例,计算了XY面上自旋关联函数和反铁磁磁化强度的模方,通过与密度矩阵重整化群方法计算结果作对比,验证了算法的正确性.This paper mainly introduces an algorithm for computing the off-diagonal correlation functions with directed loop update algorithm within the stochastic series expansion framework. Taking the one-dimensional Heisenberg model and the easy-plane XXZ model as examples,we calculate the spin-spin correlation function and squared staggered magnetization in the XY plane using the algorithm and validate the correction of the algorithm by comparing results with those obtained using the DMRG method.

关 键 词：量子强关联 随机序列展开 非对角关联函数 

分 类 号：O414.21[理学—理论物理]