GaAs1−xPx DIODE PUMPED YAG: Nd LASERS

Experiments using GaAs1−xPx diodes emitting at 8100 A to cw pump YAG: Nd laser rods are described. At an electrical input power of 7.6 W to an array of 4% efficient diodes operating at room‐temperature threshold was attained for a laser rod, with high‐reflectivity mirrors, cooled to 3.5°C. For a laser rod with a 0.4% transmission output mirror threshold was reached at −2.5°C. From threshold‐temperature‐dependence data for the latter rod, an extrapolation has been made showing that a straightforward increase in the number of diodes by a factor of 3 to 4 will result in threshold being exceeded by 2 to 3 times at a rod temperature of 20°C.