TEMPERATURE DEPENDENCE OF PARAMAGNETIC RELAXATION AT POINT DEFECTS IN VITREOUS SILICA.
Abstract
Spin relaxation has been measured at 3 kOe and at lattice temperatures from 1.24K to 250K for the E' centers generated in one type of vitreous silica by 2 MeV gamma rays. An unusual temperature dependence was found in which the spin-lattice relaxation time varies roughly as T to the minus 2.5 power over most of the range. All of the data are accurately fitted by analytical functions derived from a coupling of the individual defect centers to the vitreous host involving excess local strain due to mechanical resonances of about 4.1 x 10 to the 11th power cps and 6.0 x 10 to the 12th power at each E' center. The strength of the coupling and the characteristic frequencies of mechanical resonance are similar to those in crystalline SiO2. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 17, 1964
- Accession Number
- AD0608625
Entities
People
- D. W. Feldman
- J. G. Castle Jr.