A thermodynamic approach to linear cross-talk in multimode fiber systems

TL;DR

This paper extends optical thermodynamic theory to low-power multimode fiber systems, providing a simple model to describe power exchange and steady-states, bridging classical and quantum optics for improved system design.

Contribution

It introduces a thermodynamic framework for modeling mode coupling in multimode fibers, applicable at both classical and quantum power levels, and demonstrates steady-state distributions experimentally.

Findings

Low-power multimode fibers reach steady-states described by Bose-Einstein distributions.

The thermodynamic model accurately predicts power exchange dynamics.

The approach bridges classical and quantum optics in multimode systems.

Abstract

Optical thermodynamic theory is extended to low-power multimode fiber systems to characterize with simple thermodynamic models the complex scenario of power exchange induced by random mode coupling between propagating modes. It is theoretically and experimentally demonstrated that low-power multimodal systems can give rise to steady-states described by a weighted Bose-Einstein modal power distribution. The theory applies also at quantum power level, indicating that optical thermodynamics and quantum optics coexist, allowing the study of multimodal optical systems in both classical and quantum regimes and simplifying the design of SDM systems.