Spin-wave resonances in antiferromagnets

Spin-wave resonances with record high wave numbers (n similar to 100-1000), corresponding to wave vectors k similar to 10(5)-10(6) cm(-1), have been observed in thin plates of FeBO3. Studies of the spin-wave resonances provide information on the spin wave spectrum. The temperature dependence of the inhomogeneous exchange constant has been determined for FeBO3. For temperatures higher than 1/3 of the Neel temperature the magnon spectrum is observed to undergo considerable softening, apparently as a result of their interaction. The efficiency with which spin-wave resonances are excited is found to depend significantly on inhomogeneous elastic deformations that have been artificially created in the sample. A model is proposed to describe the experimental results. (c) 2010 American Institute of Physics. [doi:10.1063/1.3490859]