二维正方晶格Compass-XY模型的方向序和拓扑序

计算物理 ›› 2016, Vol. 33 ›› Issue (2): 229-233.

二维正方晶格Compass-XY模型的方向序和拓扑序

李玉山^1,2, 万文芝²

1. 菏泽学院物理系, 山东菏泽 274015;
2. 北京科技大学物理系, 北京 100083

收稿日期:2014-12-08 修回日期:2015-04-07 出版日期:2016-03-25 发布日期:2016-03-25
作者简介:LI Yushan (1980-),male,PhD,associate professor,major in condensed matter physics,E-mail:lysh507@163.com
基金资助:
Supported by National Natural Science Foundation of China （11074021） and Science and Technology Research Program for Colleges and Universities of Shandong Province,China （J15LJ55）

Directional and Topological Orders in a Two-Dimensional Compass-XY Model on a Square Lattice

LI Yushan^1，2, WAN Wenzhi²

1. Department of Physics, Heze University, Heze 274015, China;
2. Department of Physics, University of Science and Technology Beijing, Beijing 100083, China

Received:2014-12-08 Revised:2015-04-07 Online:2016-03-25 Published:2016-03-25
Supported by:
Supported by National Natural Science Foundation of China (11074021) and Science and Technology Research Program for Colleges and Universities of Shandong Province,China (J15LJ55)

摘要/Abstract

摘要： 采用Monte Carlo方法研究二维正方晶格Compass-XY模型，通过调节过渡参量α，计算了降低交换相互作用的阻挫对方向序和拓扑序的影响.结果表明，方向序和拓扑序之间的转变是一个逐渐过渡的过程，并不存在明显的界限.在某一范围内，这两种序是相互重叠的，难以区分.阻挫的降低，易于形成拓扑序，同时会抑制方向序.当阻挫变得足够弱时，方向序被破坏.

关键词: 方向序, 拓扑序, Compass-XY模型

Abstract: Two-dimensional Compass-XY model on a square lattice is investigated by means of Monte Carlo method. Effects of decreasing frustration of exchange interactions on directional and topological orders are studied by adjusting crossover parameter α. It is demonstrated that crossover between directional and topological orders is a gradual process,which means that there is no distinct barrier. Two kinds of ordering are partly overlapped within a certain range,making it difficult to tell them apart. Decrease of frustration facilitates topological order while suppressing directional order. Directional order may be destroyed as frustration is weak enough.

Key words: directional order, topological order, Compass-XY model

中图分类号:

O469

李玉山, 万文芝. 二维正方晶格Compass-XY模型的方向序和拓扑序[J]. 计算物理, 2016, 33(2): 229-233.

LI Yushan, WAN Wenzhi. Directional and Topological Orders in a Two-Dimensional Compass-XY Model on a Square Lattice[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2016, 33(2): 229-233.

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