变形的一维半满t-J_⊥-J_z-V模型的量子相图研究（英文）  

Quantum Phase Diagram of the One-dimensional Extended t-J Model with Inter-site Coulomb Repulsion and Anisotropic Exchange

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：《四川师范大学学报（自然科学版）》2016年第2期254-261,共8页Journal of Sichuan Normal University（Natural Science）

基　　金：This work is supported by NSFC(11265015,11347207,11404276 and 11564038);NSF of the Xinjiang Uygur Autonomous(2014211A003)region(2014211A003)~~

摘　　要：借助于变形玻色算符手段、费米-玻色转化技术及重整化技术,研究了在依赖自旋的最近邻磁交换作用下,一维半满t-J扩展模型（t-J⊥-Jz-V）的弱耦合量子相图.相图显示,来自最近邻格点间各向向异性自旋交换作用（J⊥-Jz）和库仑斥力作用（V）的相互竞争使得此扩展模型基态总呈现绝缘密度波的关联行为,并且此模型量子相图的拓扑结构可通过特征参数（V/tδ^2）c=4/π来刻画,这里参数δ∈（0,1]表征玻色算符形变程度.一旦甩掉作用V（较弱的库仑作用,以致可略去）,此模型基态则会呈现绝缘相向金属相间的转变.有望此结果能为理解一维强关联t-J系统及其扩展提供了一种图景和参考.A one-dimensional half-filled extended t-J⊥-Jz-V model is studied by the deformed Hubbard operator method in the weak-coupling regime,and the quantum phase diagram is obtained via the bosonization and the renormalization group techniques.The ground state is always dominated in the insulating density-wave phases by interplay between inter-site repulsion（V） and anisotropic antiferromagnetic exchange（J⊥-Jz）.The properties of the model is determined by the parameter（V/tδ^2）c=4/π,where δ is a deformation parameter 0〈δ≤1.Moreover,when V is absent,a insulator-metal transition takes place in the system.The result provides an important insight into the t-J model and its extended versions.

关 键 词：变形t-J⊥-Jz-V模型 玻色化 变形玻色算符 重整化群 量子相图 

分 类 号：O469[理学—凝聚态物理]