Interband optical properties of silicon [001] quantum wells using a two-conduction-band k • p model

Using analytical k center dot p calculations, we are able to describe the zone-center interband optical properties of Si [001] quantum wells in agreement with first principle calculations. Within the k center dot p band formalism, we understand how the sp*-like character of the conduction band minimum determines a total anisotropy of the polarization. Similarly, its indirect gap nature generates atomic-scale oscillations of the optical matrix elements, which suggests a giant variability of the absorption. Our results are also in agreement with photoluminescence experiments on ultrathin Si/SiO2 films. (C) 2011 American Institute of Physics. [doi:10.1063/1.3663974]