TEMPERATURE AND FREQUENCY-DEPENDENCE OF THE SPIN-LATTICE RELAXATION-TIMES OF E'(1) CENTERS IN NEUTRON-IRRADIATED QUARTZ GLASS

Results are reported for measurements of the spin-lattice relaxation t imes of E-1 ' centers in quartz glass, produced by neutron irradiation , with the measurements made at two frequencies 9.25 and 24.0 GHz over a wide temperature interval 1.5-300 K. The experimental data are inte rpreted on the basis of interaction mechanisms of the spins with two-l evel systems with excitation energies similar to 6, similar to 26, and similar to 420 cm(-1). A small modification of the existing theory al lows us to explain a number of features of the observed temperature an d frequency dependence of the relaxation rate. The results are compare d with the data available in the literature on spin-lattice relaxation of irradiation centers in crystalline quartz and quartz glass. (C) 19 97 American Institute of Physics.