SENSITIZED FLUORESCENCE OF RARE EARTH IONS IN CRYSTALS.
Abstract
In order to improve the efficiency of optically pumped crystalline laser materials, a search was conducted to discover combinations of crystalline hosts, rare earth ions, and transition metal ions in which the transition metal ions are able to absorb radiation from a pump lamp over a large spectral range and then transfer this energy to rare earth ions which fluoresce and are capable of stimulated emission. Attempts were made to sensitize the rare earth ions neodymium, holmium, thulium, and europium in the crystalline hosts yttrium aluminum garnet (YAG), calcium fluorophosphate (FAP), and gadolinium aluminum perovskite (GdAlO3). Neodymium was successfully sensitized in YAG by chromium, vanadium, and manganese. No significant sensitization of neodymium was found in FAP. Europium was not able to be sensitized in any of the crystals. Holmium and thulium are sensitized by trivalent chromium in YAG, and by higher valence state of chromium in FAP. The laser efficiency of FAP crystals doped with holmium and chromium is predicted to be high since radiation is totally absorbed from 0.5 to 1.4 microns and the energy is transferred to holmium ions. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1967
- Accession Number
- AD0833252
Entities
People
- N. T. Melamed
- R. C. Ohlmann
- R. Mazelsky
- W. E. Kramer