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