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arXiv · 1806.01717

Dynamic structure factor of disordered quantum spin ladders

M. Hörmann·P. Wunderlich·K. P. Schmidt
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Abstract

We investigate the impact of quenched disorder on the dynamical correlation functions of two-leg quantum spin ladders. Perturbative continuous unitary transformations with the help of white graphs and bond-operator mean-field theory are used to calculate the one- and two-triplon contribution of the zero-temperature dynamical structure factor. Disorder results in huge effects on quasi-particles as well as composite bound states due to localization. This leads to intriguing quantum structures in dynamical correlation functions well observable in spectroscopic experiments.

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M. Hörmann, P. Wunderlich, K. P. Schmidt. 2018-06-05. Dynamic structure factor of disordered quantum spin ladders. https://doi.org/10.1103/physrevlett.121.167201

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