Surface emitting semiconductor lasers

A description is given of the research progress in developing a vertical-cavity surface-emitting (SE) injection laser based on GaAlAs/GaAs and GaInAsP/InP systems. Ultimate laser characteristics, device design, state-of-the-art performances, possible device improvement, and future prospects will also be discussed. The authors propose a vertical-cavity surface emitting semiconductor laser. To reduce the threshold current, they improved the laser reflector and introduced a circular buried heterostructure. The microcavity structure, which is 7 mu m long and 6 mu m in diameter, was realized with a threshold of 6 mA. Thus, possibilities of an extremely low threshold current SE laser device and a densely packed two-dimensional array are suggested.<>