NUCLEAR-SPIN DIFFUSION AND PARAMAGNETIC SPIN DYNAMICS IN RARE-EARTH-DOPED PHOSPHATE-GLASSES

P-31 NMR measurements been used to study the dynamics of rare earth io ns in heavily doped phosphate laser glasses at temperatures between 2 K and 100 K. A model has been developed which describes nuclear spin l attice relaxation and linewidth broadening in terms of coupling of the electronic and nuclear magnetic moments. At low temperatures the loca l fields due to the paramagnetic ions cause significant broadening of the P-31 resonance line. The local fields establish large regions with in the samples in which nuclear spin diffusion is impossible. Electron ic relaxation parameters and crystal field splittings in the rare eart h ions have been inferred from the NMR relaxation data.