Investigations On Nonlinear Properties Of Simiconductor Quantum Well System

The quantum coherence and interference in atomic system have been extensively studied.Recently, with the development of crystal technique, the preparation of quantum wellstructure can be realized. Being new quantum coherent media, the phenomenon of quantuminterference in this system can be also observed. Comparing with atomic system, we knowthat semiconductor quantum well structures also have discrete energy levels which can becontrolled, and have an advantage of easy integration. So our work has a more practical value.In this thesis, we mainly discuss nonlinear optics about slow light and ultraslow opticalsolitons in a semiconductor quantum well structure.(1) We study the absorption and slow light effect of pulsed light in a triple semiconductorquantum well, the results show that the destructive and the constructive interference can beeffectively controlled, so we may obtain an absorption transmission for a weak probe field.Under the pulsed light with quantum well interaction, we can obtain slow light, when drivenby a control field increasing, the destructive interference due to quantum coherence takeseffect, and electromagnetically induced transparency is finally produced, and the slow lightmore clearly.(2) We study the ultraslow optical solitons in tunnel-coupled double semiconductorquantum well, in an asymmetric tunnel-coupled double semiconductor quantum well system,use a weak probe field and two controlled field to driven. We can obtain ultraslow bright anddark optical solitons. Choosing a fit absorption coefficient to balance group velocitydispersion can lead to the formation of ultraslow optical solitons of the probe field.