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arXiv · 1011.0635

Neutron scattering study of a quasi-2D spin-1/2 dimer system Piperazinium Hexachlorodicuprate under hydrostatic pressure

Tao Hong·C. Stock·I. Cabrera·C. Broholm·Y. Qiu·J. B. Leao·S. J. Poulton·J. R. D. Copley
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Abstract

We report inelastic neutron scattering study of a quasi-two-dimensional S=1/2 dimer system Piperazinium Hexachlorodicuprate under hydrostatic pressure. The spin gap Δ becomes softened with the increase of the hydrostatic pressure up to P= 9.0 kbar. The observed threefold degenerate triplet excitation at P= 6.0 kbar is consistent with the theoretical prediction and the bandwidth of the dispersion relation is unaffected within the experimental uncertainty. At P= 9.0 kbar the spin gap is reduced to 0.55 meV from 1.0 meV at ambient pressure.

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Tao Hong, C. Stock, I. Cabrera, C. Broholm, Y. Qiu, J. B. Leao, S. J. Poulton, J. R. D. Copley. 2010-11-02. Neutron scattering study of a quasi-2D spin-1/2 dimer system Piperazinium Hexachlorodicuprate under hydrostatic pressure. https://doi.org/10.1103/physrevb.82.184424

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