Department of Electronic Engineering, Okayama University of Science
Abstract
The anomaly of transverse relaxation rate of YBa_2Cu_3O_ is mainly observed at 35K and near superconducting transition. The anomaly at 35K can not be explained by dynamical factor. It is considered that the static factor causes the anomaly and it is the change of anisotropy of indirect interaction between nuclear spins because the change of shape of decay curve accompanies with the anomaly. If the interaction between electron spin and nuclear spin obeys Mila-Rice theory even in superconducting state, it is considered that the change of the anisotropy is owing to change of electron spin correlation. As for the anomaly near superconducting transition it seems to be owing to an extraordinarily slow motion such as softening
