Exact solution of a topological spin ring with an impurity  

作　　者：Xu-Chu Huang Yi-Hua Song Yi Sun 黄旭初;宋艺华;孙毅(Department of Physics,Changji University,Changji 830011,China)

机构地区：[1]Department of Physics,Changji University,Changji 830011,China

出　　处：《Chinese Physics B》2020年第6期473-478,共6页中国物理B（英文版）

基　　金：National Natural Science Foundation of China(Grant No.11664001).

摘　　要：The spin-1/2 Heisenberg chain coupled to a spin-S impurity moment with anti-periodic boundary condition is studied via the off-diagonal Bethe ansatz method.The twisted boundary breaks the U(1)symmetry of the system,which leads to that the spin ring with impurity can not be solved by the conventional Bethe ansatz methods.By combining the properties of the R-matrix,the transfer matrix,and the quantum determinant,we derive the T–Q relation and the corresponding Bethe ansatz equations.The residual magnetizations of the ground states and the impurity specific heat are investigated.It is found that the residual magnetizations in this model strongly depend on the constraint of the topological boundary condition,the inhomogeneity of the impurity comparing with the hosts could depress the impurity specific heat in the thermodynamic limit.This method can be expand to other integrable impurity models without U(1)symmetry.

关 键 词：Bethe ansatz IMPURITY topological spin ring 

分 类 号：O469[理学—凝聚态物理]