SU(N) Representation of Mode Dispersion in a Multimode Optical Fiber: Determining Principal Modes for Mode Division Multiplexing

TL;DR

This paper introduces an SU(N) algebra-based method to experimentally identify principal modes in multimode optical fibers, enhancing mode division multiplexing by reducing mode dispersion and increasing data capacity.

Contribution

It presents a novel SU(N) representation approach to determine principal modes, enabling improved mode management for higher-capacity optical communication systems.

Findings

Successfully predicts higher-order Stokes parameters

Enables measurement of principal modes at fiber input/output

Facilitates decoherence-free subspace applications

Abstract

A method is proposed to experimentally determine principal modes for mode division multiplexing in a multimode optical fiber, i.e., increasing optical fiber information capacity via higher-order transverse eigenmodes. Principal modes are a special linear combination of eigenmodes that do not exhibit mode dispersion up to first order in frequency. This method is based on an SU(N) representation of mode dispersion whereby the generators of the corresponding SU(N) Lie algebra, i.e., generalized Gell-Mann matrices, predict higher-order Stokes parameters which can be used to measure principal modes at the optical fiber input and output. Applications of the SU(N) representation to decoherence free subspaces for single photon entanglement in higher-dimensional Hilbert spaces is discussed.