Work

Intermodal Raman Scattering between Orbital Angular Momentum Modes in Optical Fibers

Year: 2020

Type: conference-paper

Abstract: This paper presents an experimental and theoretical analysis of Raman amplification of OAM modes i.e. beams carrying orbital angular momentum and spin angular momentum. We show that simple scalar equations are sufficient to describe the Raman interaction between OAM modes when working in a cyclic basis. The equations are similar to those used when considering Raman amplification in conventional fibers used for optical communication. Such fibers are typically single mode and support propagation of LP modes i.e. light that is linearly polarized. In fibers that support propagation of OAM modes as well as in fibers that support propagation of LP modes the scalar equations apply when considering very short- fiber lengths or long fiber lengths, only the proper gain efficiency needs to be used. Here, we discuss the gain efficiency, its material and modal dependencies and we demonstrate that the Raman gain efficiency among OAM modes in comparison with the efficiency among LP modes mainly differs due to a typically larger mode size of OAM modes relative to that of the fundamental LP modes in conventional fibers used for optical communication. In addition, we demonstrate a mode dependent loss in an optical fibers that support propagation of OAM modes.

Source: International Conference on Transparent Optical Networks

DOI: 10.1109/icton51198.2020.9203012

Authors: Karsten Rottwitt, Neethu Mariam Mathew, Lars Gruner-Nielsen, Lars Rishoj

Institution: Technical University of Denmark

Language: English

Topic: Orbital Angular Momentum in Optics

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Research Foundation, Danmarks Grundforskningsfond, Danmarks Frie Forskningsfond

Awards: G2879367669, G6021147919, G6100286159