Phys.org March 8, 2019
The optical vortex carries the orbital angular momentum of light and can be used to multiplex signals by assigning each signal to a light wave of different momentum. Researchers in Japan designed and fabricated an orbital angular momentum multiplexing/demultiplexing module that could take five independent signals as input. Using a combination of two tiny circuit structures, called a star coupler and an optical-vortex generator, each of the five signals is “encoded” with a unique optical angular momentum. The output signal consists of a combination of the five signals, and the receiver circuit carries out the multiplexing operation in reverse (demultiplexing) to end up again with the five independent signals. The tips of the waveguides of the optical-vortex generator were made of silicon and measured a few micrometers. Such devices will be crucial for improving optical networks…read more. TECHNICAL ARTICLE
The multiplexing/demultiplexing module fabricated employs optical vortex to transmit/receive multiple signals simultaneously through a shared optical medium. Credit: The Optical Networking and Communication Conference & Exhibition 2019