Auger up-conversion processes can allow photovoltaic devices to harvest low-energy solar photons that are not normally absorbed. A team of researchers from the Los Alamos Laboratory in New Mexico in the US has now demonstrated such a process in thick-shell lead selenide/cadmium selenide semiconducting quantum dots in which two low-energy, core-based excitons (electron-hole pairs) are converted into a single, higher-energy shell-based exciton. Devices made from such nanostructures could efficiently up-convert light at infrared wavelengths that has an intensity as low as a few watts per square centimetre………
http://nanotechweb.org/cws/article/tech/67331
