Researchers at Linköping University and Shenzhen University have shown how inorganic perovskites can be used to produce low-cost and efficient photodetectors that transfer both text and music. "It's a promising material for future rapid optical communication," says Feng Gao, researcher at Linköping University.
"Perovskites of inorganic materials have a huge potential to influence the development of optical communication. These materials have rapid response times, are simple to manufacture, and are extremely stable." says Feng Gao.
All optical communications require rapid and reliable photodetectors - materials that can capture a light signal and convert it into an electrical signal. Current optical communication systems use photodetectors made from materials like silicon and indium gallium arsenide, that are expensive - partly because they are complicated to manufacture. Moreover, these materials cannot to be used in mechanically flexible, light-weight or large-area devices.
Perovskites posses impressive light-emitting properties and are easy to manufacture. For applications such as light-emitting diodes and efficient solar cells, most interest has been placed on perovskites that consist of an organic substance (containing carbon and hydrogen), metal, and halogen (fluorine, chlorine, bromine or iodine) ions. However, when this composition was used in photodetectors, it proved to be too unstable.
The results changed, however, when the researchers used the right materials, and managed to optimize the manufacturing process and the structure of the film. The film in the new perovskite, which contains only inorganic elements (caesium, lead, iodine and bromine), has been tested in a system for optical communication, which confirmed its ability to transfer both text and images, rapidly and reliably. The quality didn't deteriorate, even after 2,000 hours at room temperature.
"It's very gratifying that we have already achieved results that are very close to application," says Feng Gao.