Multiphoton Sub-Band-Gap Photoconductivity and Critical Transition Temperature in Type-II GaSb Quantum-Dot Intermediate-Band Solar Cells

Abstract

Quantum dots can provide electronic states that act as ``stepping stones'' in absorbing light, thereby improving the efficiency of solar cells. The authors identify a transition temperature at which a significant gain in solar energy absorption is seen in GaSb/GaAs quantum dots, and show that this gain is due to a particular alignment of bands in the underlying electronic structure. Related behaviors could also be valuable in optoelectronics and quantum information processing.