Fava Michele, Biswas Sounak, Gopalakrishnan Sarang, Vasseur Romain, Parameswaran S A
Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom;
Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom.
Proc Natl Acad Sci U S A. 2021 Sep 14;118(37). doi: 10.1073/pnas.2106945118.
We develop a formalism for computing the nonlinear response of interacting integrable systems. Our results are asymptotically exact in the hydrodynamic limit where perturbing fields vary sufficiently slowly in space and time. We show that spatially resolved nonlinear response distinguishes interacting integrable systems from noninteracting ones, exemplifying this for the Lieb-Liniger gas. We give a prescription for computing finite-temperature Drude weights of arbitrary order, which is in excellent agreement with numerical evaluation of the third-order response of the XXZ spin chain. We identify intrinsically nonperturbative regimes of the nonlinear response of integrable systems.
我们开发了一种用于计算相互作用可积系统非线性响应的形式体系。我们的结果在流体动力学极限下是渐近精确的，即在该极限下微扰场在空间和时间上变化足够缓慢。我们表明，空间分辨的非线性响应将相互作用的可积系统与非相互作用的系统区分开来，以利布 - 林格气体为例进行了说明。我们给出了计算任意阶有限温度德鲁德权重的方法，该方法与XXZ自旋链三阶响应的数值评估结果高度吻合。我们确定了可积系统非线性响应的内在非微扰区域。
