Title :
High-inversion densities in Nd:YAG-upconversion and bleaching
Author :
Guy, S. ; Bonner, C.L. ; Shepherd, D.P. ; Hanna, D.C. ; Tropper, A.C. ; Ferrand, B.
Author_Institution :
Dept. de Phys. des Mater., Univ. Claude Bernard, Villeurbanne, France
fDate :
5/1/1998 12:00:00 AM
Abstract :
We report on the investigation of upconversion in Nd:YAG and its implications for intensely pumped devices. Analysis of lifetime measurements and the performance of a 1 at.% Nd-doped YAG amplifier give an Auger upconversion rate of 7×103 s-1. This is significantly smaller than previously reported, but modeling of the performance of Nd:YAG devices with high-inversion densities shows that even this rate can still seriously degrade the small-signal gain and significantly increase the thermal load. The variation of cross-relaxation and upconversion rates with doping level is also described. Finally, it is found that the effect of bleaching of the Nd:YAG absorption can lead to a reduced spatial overlap between the signal and inversion profiles and thus can also significantly reduce the gain
Keywords :
Auger effect; neodymium; optical pumping; optical saturable absorption; radiative lifetimes; solid lasers; Auger upconversion rate; Nd-doped YAG amplifier; Nd:YAG absorption; Nd:YAG laser material; Y:Nd; bleaching; cross-relaxation; doping level; high-inversion densities; intensely pumped devices; inversion profiles; laser gain reduction; lifetime measurements; reduced spatial overlap; small-signal gain; thermal load; upconversion; upconversion rates; Bleaching; Diodes; Laser excitation; Neodymium; Optical materials; Planar waveguides; Pump lasers; Semiconductor laser arrays; Stationary state; Waveguide lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
