Radial mode dependence of optical beam shifts

TL;DR

This paper investigates how higher-order radial modes in LG beams affect optical beam shifts, revealing that angular shifts increase with radial mode index while positional shifts remain unaffected, supported by theoretical and experimental results.

Contribution

It is the first study to analyze the impact of higher-order radial modes on optical beam shifts in LG beams, expanding understanding of mode-dependent beam behavior.

Findings

Angular shifts are enhanced by the radial mode index p.

Positional shifts are unaffected by p.

Results enable prediction of beam shifts for arbitrary LG modes.

Abstract

It is known that orbital angular momentum (OAM) couples the Goos-Hanchen and Imbert-Fedorov shifts. Here, we present the first study of these shifts when the OAM-endowed LG(l,p) beams have higher-order radial mode index (p>0). We show theoretically and experimentally that the angular shifts are enhanced by p while the positional shifts are not. Since LG(l,p) modes form a complete basis set for paraxial beams, our results can be used to predict beam shifts of arbitrary modes of light.