Abstract

We have reported that in aysmmetric mirror reflectivity GaInAsP/InP DFB laser, a high single longitudinal mode (SLM) operation yield was achieved by adjusting a KL to to be 0.5 to 1 and a power reflectivity of a low reflecting end to be 0.05 when the other end is as cleaved [1]. This is because that an axial hole burning effect which breaks SLM operation at high output power is not serious as to reduce the gain difference. In such a weakly coupled case, there is a possibility of unnecessary Fabry-Perot (FP) mode lasing due to a mismatch between a gain peak wavelength and a lasing wavelength of DFB mode when a temperature is changed. Here we have examined an effect of the mismatch for 1.3µm DFB lasers, and made clear an optimum region of the wavelength mismatch. With this optimization, low threshold high efficiency DFB lasers with high SLM operation yield over a wide temperature range have been realized.

© 1987 Optical Society of America