Enhanced performances of Nd-activated self-nonlinear devices

摘要

The paper discusses the basic possibilities for enhancement of the output power of the self-frequency-doubling devices based on Nd-activated nonlinear crystals, by acting on the factors that determine the intracavity intensity at the fundamental frequency. It is inferred that a very important factor of improvement is the increase of the quantum defect ratio at the fundamental frequency by pumping directly into the emitting level. The relation between the conditions that enhance the intracavity intensity and the frequency-doubling performances is discussed and verified by the marked enhancement of emission at 530 nm in Nd:GdCa_4O(BO_3)_3 with direct pumping at 887 nm.