Quantum Interference Effect and Electric Field Domains in Multiple Quantum Well Structures

There has been great interest in studying optical and transport properties of multiple quantum well (MQW) structures. In these “artificial molecules”, energy quantization and the wave nature of the carriers have been used to design new devices, e.g., intersubband lasers. The understanding of carrier transport in MQWs is important for the design of lasers with high modulation speed. In this talk, we report on a new observation of a quantum interference effect in the photocurrent spectrum of weakly coupled bound-to-continuum MQWs. Using this effect, we analyze the electric field domain (EFD) formation in the superlattice [1].