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Quantum Statistics of Interacting Dimer Spin Systems

Ch. Rüegg·B. Normand·M. Matsumoto·Ch. Niedermayer·A. Furrer·K. W. Krämer·H. U. Güdel·Ph. Bourges·Y. Sidis·H. Mutka
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Abstract

The compound TlCuCl3 represents a model system of dimerized quantum spins with strong interdimer interactions. We investigate the triplet dispersion as a function of temperature by inelastic neutron scattering experiments on single crystals. By comparison with a number of theoretical approaches we demonstrate that the description of Troyer, Tsunetsugu, and Wuertz [Phys. Rev. B 50, 13515 (1994)] provides an appropriate quantum statistical model for dimer spin systems at finite temperatures, where many-body correlations become particularly important.

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Ch. Rüegg, B. Normand, M. Matsumoto, Ch. Niedermayer, A. Furrer, K. W. Krämer, H. U. Güdel, Ph. Bourges, Y. Sidis, H. Mutka. 2005-10-18. Quantum Statistics of Interacting Dimer Spin Systems. https://doi.org/10.1103/physrevlett.95.267201

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