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Spin-wave spectrum of copper metaborate in the commensurate phase 10K<T<21K

M. Boehm·S. Martynov·B. Roessli·G. Petrakovskii·J. Kulda
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Abstract

We have investigated the spin-wave spectrum of copper metaborate, CuB$_2$O$_4$, by means of inelastic neutron scattering in the commensurate magnetic phase. We have found two branches of spin-wave excitations associated with the two magnetic sublattices Cu(A) and Cu(B), respectively. In the temperature regime $10K \le T \le 21K$, where only the Cu(A) magnetic moments are ordered, the interaction between the two sublattices is found to be negligible. With this approximation we have determined the `easy plane' exchange parameters of the Cu(A) subsystem within standard spin-wave theory.

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M. Boehm, S. Martynov, B. Roessli, G. Petrakovskii, J. Kulda. 2002-03-19. Spin-wave spectrum of copper metaborate in the commensurate phase 10K<T<21K. https://doi.org/10.1016/s0304-8853(02)00415-8

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