NONLINEAR OPTICAL-PROPERTIES OF GAAS/GAAIAS MULTIPLE QUANTUM WELL MATERIAL - PHENOMENA AND APPLICATIONS

Semiconductor microstructures whose dimensions are comparable to atomic dimensions and whose interfaces are atomically smooth exhibit novel optical properties not encountered in the parent compounds. Quantum well structures, which consist of ultrathin semiconductor layers alternately grown one on the other, possess remarkable optical nonlinearities and electro-optical properties with potential applications in optoelectronics. This paper reviews the studies of GaAs/AlGaAs quantum well structures (QWS), briefly discusses the physics of absorption in QWS at room temperature, and describes the mechanisms of saturation of excitonic absorption and refraction and that of electroabsorption in QWS. Finally, the applications of these effects to optical processing and optoelectronic devices are reviewed.