Wave Function Engineering of Linear and Non-Linear Optical Response in Si-Ge Quantum Well Structures and Superlattices

Abstract

ABSTRACTWe show that the infinite Si-Ge superlattices predicted to exhibit strong optical transitions across the fundamental gap and between conduction subbands also give rise to significant optical nonlinearities. Efficient optical transitions can also be achieved in finite-length structures grown on Si or Ge substrates. However, the zone folding argument does not apply and the electronic structure strongly reflects the finite length of such systems.