Detection of Bessel beams with digital axicons

TL;DR

This paper introduces a digital method for detecting Bessel beams with various indices using a spatial light modulator, achieving high fidelity and enabling analysis of beam behavior under obstructions and turbulence.

Contribution

A novel all-digital detection technique for Bessel beams with low cross-talk, applicable to complex propagation scenarios.

Findings

Detection cross-talk below 5% for high OAM fields

Successful observation of modal spectrum changes during self-reconstruction

Effective characterization of Bessel beam distortions in turbulence

Abstract

We propose a simple method for the detection of Bessel beams with arbitrary radial and azimuthal indices, and then demonstrate it in an all-digital setup with a spatial light modulator. We confirm that the fidelity of the detection method is very high, with modal cross-talk below 5%, even for high orbital angular momentum carrying fields with long propagation ranges. To illustrate the versatility of the approach we use it to observe the modal spectrum changes during the self-reconstruction process of Bessel beams after encountering an obstruction, as well as to characterize modal distortions of Bessel beams propagating through atmospheric turbulence.