Coupling Light to Higher Order Transverse Modes of a Near-Concentric Optical Cavity

TL;DR

This paper demonstrates the use of a spatial light modulator to efficiently couple light into multiple higher-order transverse modes of a near-concentric optical cavity, enabling advanced multi-mode light-atom interaction studies.

Contribution

It introduces a method to shape incoming light to match multiple LG modes in a near-concentric cavity, achieving high coupling efficiency.

Findings

Coupling efficiency close to theoretical predictions for single LG modes.

Effective shaping of light to match multiple LG modes.

Alignment imperfections limit maximum efficiency.

Abstract

Optical cavities in the near-concentric regime have near-degenerate transverse modes; the tight focusing transverse modes in this regime enable strong coupling with atoms. These features provide an interesting platform to explore multi-mode interaction between atoms and light. Here, we use a spatial light modulator (SLM) to shape the phase of an incoming light beam to match several Laguerre-Gaussian (LG) modes of a near-concentric optical cavity. We demonstrate coupling efficiency close to the theoretical prediction for single LG modes and well-defined combinations of them, limited mainly by imperfections in the cavity alignment.