Researchers from the University of Minnesota have found that a thin black phosphorus film allows for high-speed data communication on nanoscale optical circuits. Black phosphorus is a crystaline form of phosphorus. Due to its unique properties, black phosphorus can be used to detect light very effectively. The researchers were able to create intricate optical circuits in silicon and laid thin flakes of black phosphorus over the structures. The devices showed vast improvement in efficiency over comparable devices using graphene. The researchers demonstrated that the performance of the black phosphorus photodetectors rivals that of comparable germanium devices, which is the gold standard in on-chip photodetection. However, the germanium is difficult to grow on silicon optical circuits, while black phosphorus can be grown separately and transferred onto any material. When the researchers used the black phosphorus photodetectors to recover data sent over optical fiber, they were able to demonstrate data speeds up to 3 gigabits per second.
Source: University of Minnesota