Submillimeter wave ESR measurements of the ABX3 triangular antiferromagnet CsMnBr3 with easy-plane type anisotropy have been performed in the frequency region from 9 to 383.3 GHz. The frequency-field relations of AFMR observed below TN = 8.3 K are analyzed by the molecular field theory using six sublattice model. To explain the AFMR modes, it is necessary to consider the diagonal interchain interaction J2 as in the cases of the easy-axis type triangular antiferromagnets.
- ABX triangular antiferromagnet
- Diagonal interchain interaction
- Easy-plane anisotropy
- One-dimensional antiferromagnet
- Submillimeter wave ESR