依赖自旋的一维半满扩展Hubbard模型的基态相图演化（英文）  

Evolution of Ground State Orderings in One-dimensional Extended t-U-V_⊥-V_|| Hubbard Chain

作　　者：林二印[1] 丁汉芹[1] 张军[1,2] 

机构地区：[1]新疆大学物理科学与技术学院,新疆乌鲁木齐830046 [2]中国科学院理论物理研究所理论物理国家重点实验室,北京100190

出　　处：《新疆大学学报（自然科学版）》2015年第2期134-139,156,共7页Journal of Xinjiang University(Natural Science Edition)

基　　金：supported by NSFC Project(11265015,11347207,11365021 and 11404276)

摘　　要：在场论的框架下,利用费米–玻色转化技术及重整化技术,研究了在弱耦合条件下,依赖自旋的最近邻相互作用下的一维半满Hubbard(U-V⊥-V||)扩展模型基态的相图演化行为.结果显示,随着相对偏离参数δ的增大,基态相图中的SDW±关联和SDWz关联分别增强;然而bd-SDW±关联和CDW关联依次减弱.这意味着,依赖自旋的最近邻相互作用在多电子系统中可能是真实的,它的存在为理解一维强关联系统中绝缘相(CDW,SDW±,z和bdSDW±,z)的竞争提供了一种图景和参考.A half-filled one-dimensional extended （U-V⊥-V｜） Hubbard chain with nearest-neighbor spin-dependent repulsion （V⊥, V｜ 〉0） in the weak-coupling regime has been considered, combining the bosonization with the renormal-ization group method to obtain phase topological structures. The results show that a strong enhancement of tendencies towards SDW± and SDWz phases is caused by the competition between the spin-independent interactions related to the case of V⊥ and V｜ repulsion, respectively, with the relative deviation parameterδincreasing, but bd-SDW± and CDW orderings gradually vanish in the electron system in this case. Such a result indicates that nearest neighbor spin-dependent repulsion might present in a more realistic electron system, providing a further insight into the competition for insulating CDW, SDW±, z and bd-SDW±, z orderings in the quasi-1D strongly correlated physics.

关 键 词：依赖自旋的最近邻斥力 玻色化 重整化群 相图 

分 类 号：O469[理学—凝聚态物理]