1.5 µm wavelength distributed reflector laserswith vertical grating

A 1.5 µm wavelength distributed reflector laser, consisting of a distributed Bragg reflector rear facet and a distributed feedback region, was realised using deep-etching technology. A low threshold current of Ith = 12.4 mA and a high differential quantum efficiency of ηd = 42% from the front facet was achieved with a submode suppression ratio of 33 dB (I = 2.4Ith) for a fifth-order grating, 220 µm long and 6 µm wide device at room temperature.