Optical Transitions in a Self-Assembled Ge Quantum Dot/Si Superlattice Measured by Photoreflectance Spectroscopy

Abstract

We report the first room-temperature photoreflectance (PR) measurement for self-assemble Ge quantum dot/Si superlattice grown by chemical vapor deposition (CVD) system. The relevant critical energies of transitions are obtained through fitting the PR spectrum. They are in good agreement with the result of theoretical calculations for the wetting layer with strain and a quantum dot of disk shape.