Y. Tohmori

Novel Structure GaInAsP/InP 1.5–1.6 µm Bundle Integrated-Guide (BIG) Distributed Bragg Reflector Laser

A novel structure, 1.5–1.6 µm GaInAsP/InP bundle integrated guide (BIG) distributed Bragg reflector (DBR) laser is presented. The device was operated under CW condition at room temperature with low threshold current. Stable single mode operation was obtained at up to twice the threshold current. The significance of this structure is that the step at the joint between two waveguide regions, such as the active and passive DBR regions, is negligible which results in easy fabrication of buried heterostructure. Theoretical high coupling efficiency of 95–99% with largr fabrication tolerance and higher optical confinement in the active layer is possible.

1.55 μm Butt-Jointed Distributed Bragg Reflector Lasers Grown Entirely by Low-Pressure MOVPE

1.55 µm distributed Bragg reflector lasers were fabricated entirely by low-pressure MOVPE growth. An active waveguide was connected to a passive waveguide by a butt-joint technique. In the butt-jointed structure, the optical field axis in the active region was matched to that in the passive region. Devices fabricated were operated at currents as low as 13 mA. Spectrum linewidth as narrow as 3.4 MHz was obtained at four times the threshold current.