Long range propagation of optical vortex beams in atmospheric turbulence

Abstract

Remote laser detection requires laser beam propagation through often unfavorable real-world atmospheric conditions. Turbulence is one of the main factors causing the beam to get distorted and lose its integrity and has direct implications on our ability to detect spectroscopic signatures remotely. One method to suppress turbulence effects is the use of vortex beams which have a spiral phase structure and carry the orbital angular momentum (OAM). Vortex beams are generally considered to be more robust against the turbulence effects compared to conventional Gaussian beams. However, the actual vortex beam performance in remote sensing is also heavily dependent on the exact mode of vortex beam family it belongs to. In this work, we simulate the propagation of beams to a distance of 100 meters under controlled turbulence and compared the performance of a conventional Gaussian beam to two different modes of vortex beams: Hypergeometric Gaussian (HyGG) and Laguerre Gaussian (LG) beams. Through detailed evaluation of the beam circularity as a quantitative metric for beam propagation under turbulence, we demonstrate that HyGG vortex beams exhibit improved resistance against turbulence when compared to conventional Gaussian beams and LG vortex beams. This work provides insights toward a more comprehensive understanding of how vortex beams benefit long-range remote detection and identifying new strategies for long propagation-range propagation of tailored laser beams.