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A neutron scattering study of two-magnon states in the quantum magnet copper nitrate

D. A. Tennant·C. Broholm·D. H. Reich·S. E. Nagler·G. E. Granroth·T. Barnes·K. Damle·G. Xu·Y. Chen·B. C. Sales
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Abstract

We report measurements of the two-magnon states in a dimerized antiferromagnetic chain material, copper nitrate (Cu(NO3)2*2.5D2O). Using inelastic neutron scattering we have measured the one and two magnon excitation spectra in a large single crystal. The data are in excellent agreement with a perturbative expansion of the alternating Heisenberg Hamiltonian from the strongly dimerized limit. The expansion predicts a two-magnon bound state for q ~ (2n+1)pi*d which is consistent with the neutron scattering data.

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D. A. Tennant, C. Broholm, D. H. Reich, S. E. Nagler, G. E. Granroth, T. Barnes, K. Damle, G. Xu, Y. Chen, B. C. Sales. 2002-07-29. A neutron scattering study of two-magnon states in the quantum magnet copper nitrate. https://doi.org/10.1103/physrevb.67.054414

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