Fundamental 1064 nm and self-doubling laser emission in Nd:GdCOB pumped into the emitting level

Summary form only given. Self- multiplication (SM) and self-frequency-mixing (SFM) of the laser radiation in nonlinear crystals doped with laser active ions can be an important solution for construction of integrated devices that make use of the emission properties of the active ions and of the nonlinear properties of the host crystal in order to generate efficiently coherent radiation at a wavelength different from the fundamental emission of the active centers. This paper discusses some possibilities to enhance the fundamental and self-doubled laser characteristics in Nd-doped GdCOB Ca/sub 4/GdO(BO/sub 3/)/sub 3/. Large Nd:GdCOB crystals can be grown by Czochralski method from iridium crucibles. This study shows that direct pumping into the emitting level in case of the self-doubling crystals could enhance greatly the efficiency of the self-doubling emission as compared to pumping into the /sup 4/F/sub 5/2/ level, owing to the reduction of the quantum defect between the pump and laser emission wavelengths. This is accompanied by a marked reduction of the heat generated in the pumped laser material, with a beneficial effect on the stability of emission and on the scaling to higher power.Both the laser emission parameters and the heat generation in these crystals are influenced by the quantum defect between the pump and laser emission energy quanta.