# Polarization dynamics in twisted fiber amplifiers: a non-Hermitian nonlinear dimer model

## TL;DR

This paper models polarization dynamics in twisted fiber amplifiers using a non-Hermitian nonlinear dimer framework, offering insights into polarization control and potential applications in optical devices.

## Contribution

It introduces a novel isomorphism between fiber amplifier polarization dynamics and a non-Hermitian nonlinear dimer, enabling analytic solutions and optical simulations.

## Key findings

- Analytic polarization-mode dynamics derived
- Simulation of non-Hermitian Bose-Hubbard model
- Potential applications in polarization devices

## Abstract

We study continuous-wave light propagation through a twisted birefringent single-mode fiber amplifier with saturable nonlinearity. The corresponding coupled-mode system is isomorphic to a non-Hermitian nonlinear dimer, and gives rise to analytic polarization-mode dynamics. It provides an optical simulation of the semi-classical non-Hermitian Bose-Hubbard model, and suggests its use for the design of polarization circulators and filters, as well as sources of polarized light.