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arXiv · 2012.07378

Exact real-time longitudinal correlation functions of the massive XXZ chain

Constantin Babenko·Frank Göhmann·Karol K. Kozlowski·Jesko Sirker·Junji Suzuki
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Abstract

We apply the recently developed thermal form factor expansion method to evaluate the real-time longitudinal spin-spin correlation functions of the spin-$\frac{1}{2}$ XXZ chain in the antiferromagnetically ordered regime at temperature $T=0$. An analytical result containing all types of excitations in the model is obtained, without any approximations. This allows for the accurate calculation of the real-time correlation functions in this strongly interacting quantum system for arbitrary distances and times.

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Constantin Babenko, Frank Göhmann, Karol K. Kozlowski, Jesko Sirker, Junji Suzuki. 2020-12-14. Exact real-time longitudinal correlation functions of the massive XXZ chain. https://doi.org/10.1103/physrevlett.126.210602

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