63,65Cu NMR study of low-frequency spin dynamics in the infinite-layer antiferromagnetic compound SrCuO2

The spin-lattice and spin-spin relaxation times have been measured for ^63,65Cu NMR in the infinite-layer anti-ferromagnet SrCuO₂ in the ordered state for temperatures from 4.2 to 361 K. In the region of low temperatures (T≤250 K), both relaxation processes are of the same nature and the main contribution to the relaxation rate is associated with the diffusion of a small number of holes with an activation energy of ∼42 meV. In the high-temperature range (T > 250 K), contributions to the transverse relaxation rate exhibit redistribution and this relaxation process is determined predominantly by indirect interactions.