Preliminary experiments on fundamental waves and inner second harmonic generation waves of semiconductor lasers - optical feedback conditions and oscillation frequency variation

摘要

We have studied the oscillation frequency stabilization of semiconductor lasers in a 1.5 μm wavelength region using inner second harmonic generation of 1.56 μm laser light by adapting the Rb D{sub}2 absorption line as an external frequency re However, the output power of inner SHG is too weak for the frequency stabilization, so we tried to increase it by using an feedback method. This method is also effective for decreasing the oscillation width of semiconductor lasers. In this experiment, we survey two DFB lasers with various optical feedback intensity.