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arXiv · 1905.04922

High-temperature analysis of the transverse dynamical two-point correlation function of the XX quantum-spin chain

Frank Göhmann·Karol K. Kozlowski·Junji Suzuki
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Abstract

We analyse the transverse dynamical two-point correlation function of the XX chain by means of a thermal form factor series. The series is rewritten in terms of the resolvent and the Fredholm determinant of an integrable integral operator. This connects it with a matrix Riemann-Hilbert problem. We express the correlation function in terms of the solution of the matrix Riemann-Hilbert problem. The matrix Riemann-Hilbert problem is then solved asymptotically in the high-temperature limit. This allows us to obtain the leading high-temperature contribution to the two-point correlation function at any fixed space-time separation.

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Frank Göhmann, Karol K. Kozlowski, Junji Suzuki. 2019-05-13. High-temperature analysis of the transverse dynamical two-point correlation function of the XX quantum-spin chain. https://doi.org/10.1063/1.5111039

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