The light sources for optical communications in the 1.3-1.5 µm range are the quaternary InGaAsP/InP lasers which emit in this low loss region of optical fibers. The structure and properties of some lasers fabricated in this material system as well as their integration into optoelectronics are treated in this thesis.
Lasers exhibiting low threshold, high power and stable far field are extremely desirable in communication systems. Selective epitaxial growth offers an elegant yet powerful technique of fabricating laser structures with these properties. Its application to, as well as properties of, the resulting laser structures are presented. In particular, a laser with high output power is demonstrated.
To further extend the operating power of index guided laser diodes in a stable fundamental mode, gain stabilization is proposed as an effective means of discriminating against higher order transverse mode operation. The optimal design for gain stabilized fundamental mode operation is formulated theoretically and verified experimentally.
Precipitous increase of threshold current with temperature has been observed in some InGaAsP/InP lasers. Electron leakage over the heterobarrier has been identified as the cause of this abnormality. The origin as well as the control of these leaked carriers is studied.
Advances in optoelectronic integration consisting of diffraction coupled arrays and the demonstration of Laser-MISFET devices and the technique of microcleaved mirrors are described in detail.
The microcleavage technique is applied to the fabrication of very short cavity lasers. The advantages of short cavities are presented.
