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arXiv · 1010.1230

Dynamics of the two-dimensional S=1/2 dimer system (C5H6N2F)2CuCl4

Tao Hong·S. N. Gvasaliya·S. Herringer·M. M. Turnbull·C. P. Landee·L. -P. Regnault·M. Boehm·A. Zheludev
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Abstract

Inelastic neutron scattering was used to study a quantum S=1/2 antiferromagnetic Heisenberg system-Bis(2-amino-5-fluoropyridinium) Tetrachlorocuprate(II). The magnetic excitation spectrum was shown to be dominated by long-lived excitations with an energy gap as 1.07(3) meV. The measured dispersion relation is consistent with a simple two-dimensional square lattice of weakly-coupled spin dimers. Comparing the data to a random phase approximation treatment of this model gives the intra-dimer and inter-dimer exchange constants J=1.45(2) meV and J'=0.31(3) meV, respectively.

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Tao Hong, S. N. Gvasaliya, S. Herringer, M. M. Turnbull, C. P. Landee, L. -P. Regnault, M. Boehm, A. Zheludev. 2010-10-07. Dynamics of the two-dimensional S=1/2 dimer system (C5H6N2F)2CuCl4. https://doi.org/10.1103/physrevb.83.052401

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