Manipulation of polarization topology using a Fabry-P\'erot fiber cavity with a higher-order mode optical nanofiber

TL;DR

This paper demonstrates a Fabry-Pérot fiber cavity supporting higher-order modes in an optical nanofiber, revealing complex polarization topologies and enabling tunable polarization states for advanced quantum and cold atom applications.

Contribution

It introduces a novel cavity design supporting higher-order modes with complex polarization topologies, expanding the capabilities of nanofiber-based optical cavities.

Findings

Observation of complex polarization states with topological features

In situ tuning of intracavity birefringence

Potential applications in cold atom manipulation

Abstract

Optical nanofiber cavity research has mainly focused on the fundamental mode. Here, a Fabry-P\'erot fiber cavity with an optical nanofiber supporting the higher-order modes, TE01, TM01, HE21o, and HE21e, is demonstrated. Using cavity spectroscopy, with mode imaging and analysis, we observe cavity resonances that exhibit complex, inhomogeneous states of polarization with topological features containing Stokes singularities such as C-points, Poincar\'e vortices, and L-lines. In situ tuning of the intracavity birefringence enables the desired profile and polarization of the cavity mode to be obtained. These findings open new research possibilities for cold atom manipulation and multimode cavity quantum electrodynamics using the evanescent fields of higher-order mode optical nanofibers.