抄録
Nuclear transverse relaxation rates of the Cu63 and the ligand nuclei F19 and Cl35 in K2CuF4 and (CH3NH3)2CuCl4 have been studied by the pulsed NMR method in the magnetically ordered state. In a small external magnetic field the steep decrease of the relaxation rate caused by the small anisotropy field within layer as well as the two-dimensionality of these compounds has been observed. The relaxation rates due to the scattering of the electronic spin-wave (Raman process) and the indirect coupling (Suhl-Nakamura interaction) are calculated for the present nearly two-dimensional ferromagnets including the interlayer exchange interaction and the XY like anisotropy in the intralayer exchange one. It turns out that the XY like anisotropy considerably decreases the relaxation rate. The theoretical calculation agrees well with the observation.
