Griffiths-McCoy singularities in the dilute transverse-field Ising model: A numerical linked cluster expansion study
Griffiths-McCoy singularities in the dilute transverse-field Ising model: A numerical linked cluster expansion study
复制标题
稀横向场伊辛模型中的 Griffiths-McCoy 奇点：数值关联簇扩展研究
DOI：
10.1103/physreve.99.032129
复制
发表时间：
2019
影响因子：
2.4
通讯作者：
Singh, Rajiv R. P.
中科院分区：
文献类型：
--
作者：
Thompson, Foster;Singh, Rajiv R. P.
本文利用数值链团展开方法研究了在正方晶格上的格位稀释横向场伊辛模型。在团簇的边界上具有自洽平均场的NLCE被用来获得基态磁化强度、磁化率和结构因子作为横向场和交换常数的函数。在模型中加入场地稀释度，将NLCE转化为稀释度参数的级数展开。研究结构因子的发散度可以建立平面内的相图。通过研究系统在纵向磁场中的磁化强度，我们研究了Griffiths-McCoy奇异性。我们发现，在格里菲斯阶段的磁化发展的非线性指数，不断变化。此外，局部磁化率的概率分布在格里菲思阶段发展长尾，这是研究其时刻。
We use numerical linked cluster expansions (NLCEs) to study the site-diluted transverse-field Ising model on the square lattice at. NLCE with a self-consistent mean field on the boundary of the clusters is used to obtain the ground-state magnetization, susceptibility, and structure factor as a function of transverse fieldand exchange constant. Adding site dilution to the model turns NLCE into a series expansion in the dilution parameter. Studying the divergence of the structure factor allows us to establish the phase diagram in theandplane. By studying the magnetization of the system in a longitudinal field, we investigate the Griffiths-McCoy singularities. We find that the magnetization develops nonlinearities in the Griffiths phase with exponents that vary continuously with. Additionally, the probability distribution of the local susceptibility develops long tails in the Griffiths phase, which is studied in terms of its moments.