Terabit-Scale Orbital Angular Momentum Mode Division Multiplexing in Fibers

A Twist on the Capacity Crunch

The rate at which data can be transmitted down optic fibers is approaching a limit because of nonlinear optical effects. Multiplexing allows data to be encoded in different modes of light such as polarization, wavelength, amplitude, and phase and to be sent down the fibers in parallel. Optical angular momentum (OAM) can provide another degree of freedom whereby the photons are given a well-defined twist or helicity. Bozinovic et al. (p. 1545 ) were able to transmit high-bandwidth data using OAM modes in long lengths of optical fibers, thus providing a possible route to get yet more capacity through optic fiber networks.