Transmission of Orbital Angular Momentum and Cylindrical Vector Beams in a Large-Bandwidth Annular Core Photonic Crystal Fiber

Manish Sharma,Younès Messaddeq,Bora Ung,Satyendra Mishra,Dipankar Sengupta,Fatemeh Amirkhan,François Blanchard

doi:10.3390/fib8040022

Abstract

The stable propagation of orbital angular momentum and cylindrical vector beams in a newly designed annular core photonic crystal fiber (AC-PCF) tailored for the broadband single-radial order beam transmission (within the so-called “endlessly mono-radial” guiding regime) is demonstrated for the first time. It is shown that the vector-vortex beams can maintain high mode purities above 18 dB after propagation in the fiber under test over all of the wavelength range from 805 to 845 nm (over 17 THz bandwidth) investigated with the help of a tunable laser and an S-plate for the generation of singular beams in free space. Our results confirm that the AC-PCF is a promising design for the broadband transmission of vector-vortex beams that have potential applications in space-division multiplexing, quantum communications, optical sensing and trapping.

Highlights

We are still in the early stages of grasping the fundamental implications and applications of the vector-vortex beams
Polarized beam passes through quarter-wave platepolarizer (QWP),(LP)
The cylindrical vector beams (CVB) and orbital angular momentum (OAM) beam propagation in the annular core photonic crystal fiber (AC-photonic crystal fibers (PCF)) is characterized by analyzing their respective intensity profiles at the distal end of the fiber

Summary

Introduction

We are still in the early stages of grasping the fundamental implications and applications of the vector-vortex beams. A particular design of annular-core photonic crystal fiber (AC-PCF) This unique recently proposed the theoretical order abilitymodes to enforce mono-radial vector-vortex while waveguiding regime termed “endlessly mono-radial”. Regime cladding termed “endlessly occurs the periodic crystal cladding has Recently, et al(d)demonstrated vortex beam propagation inside photonic crystal holes withTandjè a diameter to pitch (Λ) ratio below a certain threshold: d/Λ a< ring. OAM demonstrated beam propagation inside ringand corethe photonic crystal fiber, the mode latter purities remained limited [28]. The Vparameter for the AC-PCF is defined as [27]: To ensure the mono-radial operation of the few-mode fiber, it is critical to prevent excitation of the. Based on the specific where a isofthe effective core radius, nfinite-element index of the solid glass material ofwere the core is the refractive geometry our AC-PCF, full-vector method simulations of the. EMR regime, which in theory applies for the whole electromagnetic spectrum

Discussion

Conclusions

Management