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arXiv · 1210.5899

Excitations in a quantum spin liquid with random bonds

D. Huvonen·S. Zhao·G. Ehlers·M. Månsson·S. N. Gvasaliya·A. Zheludev
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Abstract

We present results of inelastic neutron scattering study on two bond disordered quasi twodimensional quantum magnets (C$_4$H$_12$N$_2$)Cu$_2$(Cl$_{1-x}$Br$_x$)$_6$ with x=0.035 and 0.075. We observe the increase of spin gap, reduction of magnon bandwidth and a decrease of magnon lifetimes compared to x=0 sample. Additional magnon damping is observed at higher energies away from zone center which is found to follow the density of single particle states.

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D. Huvonen, S. Zhao, G. Ehlers, M. Månsson, S. N. Gvasaliya, A. Zheludev. 2012-10-22. Excitations in a quantum spin liquid with random bonds. https://doi.org/10.1103/physrevb.86.214408

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