However, it was another Oxford lab that amped up the visual intensity of perovskite's luminescence and discovered it wasted only 30% of the energy put into it while focusing visible light into lasers bordering on the infrared end of the spectrum.
Light hitting any solar-cell film will strip electrons from the surface, leaving minute holes in the surface that drastically reduce the amount of light it reflects, making it appear darker.
Perovskite has such a high level of photoluminescent quantum efficiency that it hardly dims at all, giving it an efficiency rate of 70% when used as the emitting surface of a vertical-cavity surface-emitting laser -- a semiconductor laser diode.
"These long carrier lifetimes together with exceptionally high luminescence yield are unprecedented in such simply prepared inorganic semiconductors and we note that these properties are ideally suited for photovoltaic diode operation," Felix Deschler of Oxford's Cavendish Laboratory wrote in the abstract of a paper published in the Journal of Physical Chemistry Letters on March 24 (registration required).
Spinoffs from the NTU and Oxford labs are already at work on versions of perovskite cells to be used in commercial applications to generate power -- or light. Researchers are racing to get out products using the new meta-material -- which became known for its photo-optic properties only in 2011 -- before the next surprising revelation about its characteristics and performance levels.
Almost accidentally, for example, the NTU lab discovered perovskite also makes a good material for computer touchscreens. The researchers are investigating how it could be incorporated into portable or wearable computer devices.