A thin-film material that converts infrared light into visible light has been unveiled by researchers at the Massachusetts Institute of Technology (MIT). Made of two non-conventional semiconductors, the material works for infrared light at moderate intensities, and could be used to improve a range of technologies including solar cells, cameras and night-vision goggles.
The team, led by Vladimir Bulović, Moungi Bawendi and Marc Baldo of the Energy Frontier Research Center for Excitonics at MIT, made its films on top of glass microscope slides. The films have a simple, two-layer structure. The bottom layer consists of colloidal quantum dots. These are nanometre-sized chunks of the semiconductor lead sulphide coated with a molecular layer of fatty acids. The top layer is a crystalline film made of an organic molecule called rubrene.