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arXiv · 1906.03143

Equilibrium dynamics of the XX chain

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

The equilibrium dynamics of the spin-1/2 XX chain is re-examined within a recently developed formalism based on the quantum transfer matrix and a thermal form factor expansion. The transversal correlation function is evaluated in real time and space. The high-accuracy calculation reproduces several exact results in limiting cases as well as the well-known asymptotic formulas obtained by the matrix Riemann-Hilbert approach. Furthermore, comparisons to numerical data based on a direct evaluation of the Pfaffian as well as to asymptotic formulas obtained within non-linear Luttinger liquid theory are presented.

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Frank Göhmann, Karol K. Kozlowski, Jesko Sirker, Junji Suzuki. 2019-10-28. Equilibrium dynamics of the XX chain. https://doi.org/10.1103/physrevb.100.155428

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