准周期调制下自旋1/2反铁磁XY模型中的晶格畸变行为  

Behaviors of lattice distortions in the spin 1/2 antiferromagnetic XY model with quasiperiodic modulation

作　　者：李鹏飞[1] 曹海静[1] 郑莉[1] 蒋秀丽[1] 

机构地区：[1]上海电力学院数理学院,上海200090

出　　处：《物理学报》2013年第15期410-413,共4页Acta Physica Sinica

基　　金：上海市教育委员会科研(创新)项目(批准号:10ZY159)资助的课题~~

摘　　要：利用严格对角化方法研究了Thue-Morse准周期调制下自旋1/2反铁磁XY模型中的晶格畸变行为.结果显示:系统中每个格点的晶格畸变幅度介于均匀分布和无序分布之间.对于较弱的准周期调制,调制强度的增加有利于晶格畸变的形成.但是,对于较强的准周期调制,调制强度的增加则阻碍晶格畸变的形成.此外,系统低能谱的能隙也明显受到准周期调制的影响.The behaviors of lattice distortions in the spin 1/2 antiferromagnetic XY model with Thue-Morse quasiperiodic modulation are investigated by the method of exact diagonalization. It is found that the lattice distortion at each site has the character intermediate between the periodic and random systems. For weaker or stronger quasiperiodic modulation, the lattice distortion may increase or decrease with strengthening of the modulation amplitude, respectively. The results also indicate that the energy gaps of ground states are strongly affected by the quasiperiodic modulation

关 键 词：晶格畸变 Thue-Morse序列 准周期调制 

分 类 号：TM27[一般工业技术—材料科学与工程]