论文标题
边界XXZ链中的多点相关函数在有限温度下
Multi-point correlation functions in the boundary XXZ chain at finite temperature
论文作者
论文摘要
我们考虑具有纵向边界场和均匀外部磁场的开放XXZ链中的多点相关函数。我们表明，在有限温度下，这些相关函数可以写在量子传输矩阵框架中，作为对热形式的总和。更精确，非常明显的是，总和的每个项都由量子传输矩阵的常规矩阵元素的简单产物乘以包含有关边界场的整个信息的唯一因素。例如，我们为距边界距离$ m $的纵向旋转单点函数提供了详细的表达式。因此，这项工作解决了在符合开放边界条件的可集成模型中建立形式扩展的长期问题。
We consider multi-point correlation functions in the open XXZ chain with longitudinal boundary fields and in a uniform external magnetic field. We show that, at finite temperature, these correlation functions can be written in the quantum transfer matrix framework as sums over thermal form factors. More precisely, and quite remarkably, each term of the sum is given by a simple product of usual matrix elements of the quantum transfer matrix multiplied by a unique factor containing the whole information about the boundary fields. As an example, we provide a detailed expression for the longitudinal spin one-point functions at distance $m$ from the boundary. This work thus solves the long-standing problem of setting up form factor expansions in integrable models subject to open boundary conditions.
