Terabit-Scale Orbital Angular Momentum Mode Division Multiplexing in Fibers

TLDR

Optical fiber capacity is nearing limits due to nonlinear effects, prompting exploration of spatial mode multiplexing to increase data throughput. The study aims to demonstrate that orbital angular momentum modes can serve as orthogonal spatial channels for data transmission in a single fiber. The authors employ OAM of light to generate orthogonal, spatially distinct data streams multiplexed within a single fiber. They achieved 400 Gbps over 1.1 km using four OAM modes at one wavelength, and 1.6 Tbps over 10 wavelengths with two modes, indicating OAM offers a promising extra multiplexing dimension for future fiber networks.

Abstract

Internet data traffic capacity is rapidly reaching limits imposed by optical fiber nonlinear effects. Having almost exhausted available degrees of freedom to orthogonally multiplex data, the possibility is now being explored of using spatial modes of fibers to enhance data capacity. We demonstrate the viability of using the orbital angular momentum (OAM) of light to create orthogonal, spatially distinct streams of data-transmitting channels that are multiplexed in a single fiber. Over 1.1 kilometers of a specially designed optical fiber that minimizes mode coupling, we achieved 400-gigabits-per-second data transmission using four angular momentum modes at a single wavelength, and 1.6 terabits per second using two OAM modes over 10 wavelengths. These demonstrations suggest that OAM could provide an additional degree of freedom for data multiplexing in future fiber networks.