Optical fiber type broadband optical vortex converter

Abstract

The invention discloses an optical fiber type broadband optical vortex converter. The converter comprises a single-mode optical fiber, a polarization controller acting on the single-mode optical fiber, a multimode optical fiber, a polarization controller acting on the multimode optical fiber, and a polarizer which is arranged at the output end of the multimode optical fiber; the output end of thesingle-mode optical fiber and the input end of the multimode optical fiber are in asymmetrical connection with each other, so that an optical vortex mode can be excited; the order of the optical vortex mode can be flexibly regulated by controlling the polarization controllers; and the working states of the polarization controllers and the polarizer can be jointly adjusted, so that remaining non-optical vortex components can be filtered out, and therefore, the purity of the optical vortex mode can be improved. The converter does not have a bandwidth-limiting structure, so that the working bandwidth of the converter is large. The optical fiber type broadband optical vortex converter of the invention can be realized by using asymmetrical welding and asymmetrical pasting, and therefore, the processing process of the converter is simple. Compared with a conventional vortex converter device, the optical fiber type broadband optical vortex converter of the invention has the advantages of significantly reduced processing difficulty, significantly reduced cost, improved working bandwidth and wide application prospect.

Description

technical field [0001] The invention belongs to the field of photonics, and more specifically relates to an optical fiber broadband optical vortex converter. Background technique [0002] Optical vortex (OV: Optical Vortex) is a kind of spiral phase The special light field of , where l can be any integer, is called the topological charge, is the azimuth angle. The light vortex is twisted and transmitted forward around the optical axis, and there is an uncertain phase singularity in the center, which is distributed in a hollow ring. In 1992, Allen et al. confirmed that each photon of the optical vortex carries an orbital angular momentum of lh, so the optical vortex is also called an orbital angular momentum (OAM: Orbital Angular Momentum) beam. Optical vortices have been and are widely used in optical trapping, optical tweezers, optical wrench, optical Various fields such as vortex knotting, rotational speed measurement and quantum information processing. In recent ye...

AI Technical Summary

Problems solved by technology

However, the existing fiber optical vortex beam generation methods also have many challenges such as difficult processing, low mode purity, and narrow bandwidth.

In particular, the problem of bandwidth limitation also exists in other non-fiber optical vortex generation schemes

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