论文标题
横向场中的有限温度和淬灭动力学来自外形因素的扩展
Finite temperature and quench dynamics in the Transverse Field Ising Model from form factor expansions
论文作者
论文摘要
我们考虑在有限温度下计算动态顺序参数两点函数的问题，以及横向场ISing链中量子淬灭后的单点函数。这两者都可以根据模型的物理激发来表达。我们开发了一个一般框架，以基于形式因素分解为部分分数进行这些总和，从而导致多个总和的分解，并允许它们渐近地评估。这自然会导致系统的低密度扩展。在后期，这些扩展可以通过决定性代表来求和到所有订单。我们的方法在相互作用的集成模型中对半本地运算符具有自然概括。
We consider the problems of calculating the dynamical order parameter two-point function at finite temperatures and the one-point function after a quantum quench in the transverse field Ising chain. Both of these can be expressed in terms of form factor sums in the basis of physical excitations of the model. We develop a general framework for carrying out these sums based on a decomposition of form factors into partial fractions, which leads to a factorization of the multiple sums and permits them to be evaluated asymptotically. This naturally leads to systematic low density expansions. At late times these expansions can be summed to all orders by means of a determinant representation. Our method has a natural generalization to semi-local operators in interacting integrable models.
