SEMICONDUCTOR RAMAN LASER WITH PUMP LIGHT WAVELENGTH IN THE 800-NM REGION

Semiconductor Raman lasers with GaP cores and AlxGa1-xP cladding layers are operated with the pump wavelengths of 840 and 895 nm. In contrast to previous results for the pump wavelength of 1.064 mum, it is observed that the lasing characteristics for 840 and 895 nm excitation are affected by the instantaneous temperature rise due to the excess absorption, which strongly depends on the stripe width. Two photon absorption and absorption via deep levels produced at the side interfaces are discussed, and the latter is suggested as the origin of the excess absorption.