Optical Guiding in 50-Meter-Scale Air Waveguides

Abstract

The distant projection of high-peak and average-power laser beams in the atmosphere is a long-standing goal with a wide range of applications. Our early proof-of-principle experiments [Phys. Rev. X 4, 011027 (2014)] presented one solution to this problem, employing the energy deposition of femtosecond filaments in air to sculpt millisecond-lifetime sub-meter-length air waveguides. Here, we demonstrate air waveguiding at the 50-m scale, 60×longer, making many practical applications now possible. We employ a new method for filament energy deposition: multifilamentation of Laguerre-Gaussian LG01 “donut” modes. We first investigate the detailed physics of this scheme over a shorter 8-m in-lab propagation range corresponding to 13 Rayleigh lengths of the guided pulse. We then use these results to demonstrate optical guiding over 45 m in the hallway adjacent to the lab, corresponding to 70 Rayleigh lengths. Injection of a continuous-wave probe beam into these waveguides demonstrates very long lifetimes of tens of milliseconds.3 MoreReceived 9 August 2022Revised 30 November 2022Accepted 7 December 2022DOI:https://doi.org/10.1103/PhysRevX.13.011006Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasAngular momentum of lightLight-matter interactionNonlinear opticsOptics & lasersUltrafast opticsInterdisciplinary PhysicsAtomic, Molecular & Optical