Electronic Raman Effect in Garnets, Tunable Infrared Lasers, and Quantum Counters.
Abstract
The Raman technique has been applied to study some basic properties of rare-earth garnets. Preliminary investigations have been performed on a tunable IR quantum counter and Ho:YIG laser. Using Raman scattering, the following were determined: (1) the phonon energy and symmetry assignments of numerous garnets (YAlG, DyAlG, YbAlG, LuAlG, YGaG, DyGaG, YbGaG, LuGaG, YIG, DyIg, ErIG, and YbIG); (2) the energy of the lower crystal-field levels (10-4000/cm) in YbAlG, YbGaG, DyAlG, DyGaG, and ErIG; (3) the dipole and exchange-field splittings of several electronic levels for DyAlG below its Neel temperature; and (4) the accuracy of the crystal-field parameters by comparing the calculated with the observed Raman intensity. The large anisotropic exchange interaction between the Fe3+ and Re3+ ions in Re:YIG can form the basis for tunable IR quantum counters and lasers. A tunable quantum counter in the 5 micrometer region is proposed by using Pr:YIG. The author has achieved laser action by optically pumping with a Nd:glass laser into the absorption band of the host crystal (YIG). Based on this achievement, it is estimated that lasing from a 100 micrometer thick slab of Ho:YIG is possible by pumping with a single GaAs laser diode.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1974
- Accession Number
- ADA003989
Entities
People
- Richard K. Chang
Organizations
- Yale University