Light emission from ordered group-IV materials: concepts and prospects

摘要

We give a survey of recent efforts to find efficient light emitters based upon crystalline group IV materials by theoretical means. While Si-based superlattices can readily be made into direct gap materials, their matrix elements for optical transitions do remain small, and even if polar intra-layers are added they nowhere near match the yardstick set by GaAs. More promising properties show up in strained Ge and the relatively novel GeSn strained layer superlattices.