The nuclear spin-lattice relaxation time of 1H in YBa2Cu3O6.9Hx (x=0.18 and 0.63) abd Bi2Sr2CaCu2O8+δHx (x=0.24 and 0.42) has been measured at 29 and 58 MHz in the temperature range between 77 and 294 K. In these compounds, the relaxation is not of a single-exponential type, but consists of two components with very short and long relaxation times. With decreasing temperature from 294 to 100 K, the relaxation rate of the long-component in each sample decreases by one order of magnitude. The relaxation rate in YBa2Cu3O6.9H0.18 is enhanced by a factor of two just below Tc and then sharply decreases, whereas that in Bi2Sr2CaCu2O8+δH0.24 drops without showing such an enhancement. The appearance of the enhancement in the former may be ascribed to the rather weak interaction of 1H in the Cu(1)-O plane with electron spin-fluctuations in the Cu(2)-O2 plane.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering