Carrier recombination in tailored multilayer Si/Si1−xGex nanostructures

Photoluminescence (PL) measurements were performed in Si/Si1−xGex nanostructures with a single Si0.92Ge0.08 nanometer-thick layer incorporated into Si/Si0.6Ge0.4 cluster multilayers. Under pulsed laser excitation, the PL decay associated with the Si0.92Ge0.08 nano-layer is found to be nearly a 1000 times faster compared to that in Si/Si0.6Ge0.4 cluster multilayers. A model considering Si/SiGe hetero-interface composition and explaining the fast and slow time-dependent recombination rates is proposed.