1.5-mum emissions from laser-diode-pumped Nd-doped microchip solid-state lasers

1.5-mum emissions from Nd:YAG, Nd:YVO(4), and LiNdP(4) O>(12) microchip lasers pumped by laser diodes have been observed. These coherent emissions are attributed to the effect of high-energy modified lattice vibration owing to the existence of Nd ions as well as to stimulated intracavity Raman scattering enhanced by the microchip configuration. A four-wave mixing process involving two lasing fields and a Stokes field was identified as the generator of new adjacent 1.5-mu;m emission.