Recovering scattered data from twisted light via `scattering-matrix-assisted retrieval technique (SMART)`
(PHYSorg.com Physics)

High-capacity optical communication can be accomplished by multiplexing multiple light-carrying orbital angular momentum (OAM) channels. However, in turbulent environments, optical scattering and `speckle patterns` occur due to ambient, atmospheric microparticles and significantly decrease the orthogonality between OAM channels, demultiplexing (extracting information) and increasing crosstalk during communication. In a recent study now published in Light: Science & Applications, Lei Gong and co-workers at the departments of optics and optical engineering, medical engineering, electrical engineering and physical sciences in China and the USA developed a `scattering-matrix-assisted retrieval technique` (SMART) to efficiently recover scattered data from multiplexed OAM channels. In the study, they used 24 OAM channels in parallel, passing through a scattering medium to demultiplex the channels from the scattered optical fields and achieve minimal experimental crosstalk approximating -13.8 dB.