An introduction to the development of the semiconductor laser.

In late 1962, the first semiconductor injection lasers were reported. While earlier workers had considered the possibility of light amplification in semiconductors, the achievement in 1962 of high-efficiency electroluminescence from forward-biased GaAs p-n junctions was the event that catalyzed and accelerated efforts to demonstrate a semiconductor laser. This paper will attempt to review the experimental and theoretical work that preceded the actual demonstration of the semiconductor diode laser.