Generation of Terahertz Superimposed Perfect Vortex Beams

Yongqiang Yang,Zhengang Yang,Tianyi Wang,Kejia Wang,Jinsong Liu

doi:10.1109/jphot.2021.3099843

Yongqiang Yang, Zhengang Yang + Show 3 more

Open Access

https://doi.org/10.1109/jphot.2021.3099843

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Abstract

A terahertz (THz) superimposed perfect vortex (SPV) beam is generated by using a designed superimposed optimal phase element (SOPE) at 0.3 THz. As the superimposed topological charge changes, the ring radius of THz SPV beams remains almost constant in the experiment, whose relative error is only 0.96%. The perfect vortex property is confirmed. The intensity profile of THz SPV beams is a ring with equally spaced breakpoints. The superimposed topological charge carried can be judged directly by identifying the number of breakpoints. The ring radius is linearly related to the radial wave vector, which can be adjusted. Such THz SPV beams have promising applications for THz fiber communication systems based on vortex beams.

Highlights

T ERAHERTZ (THz) wave, whose frequency range between microwave and infrared light wave, has the ability to provide large bandwidth and realize Tbps data rate transmission [1], [2]
The intensity profile of THz superimposed perfect vortex (SPV) beams is a ring with spaced breakpoints
The ring radius of THz SPV beams is computed by fitting the intensity profile

Summary

Introduction

T ERAHERTZ (THz) wave, whose frequency range between microwave and infrared light wave, has the ability to provide large bandwidth and realize Tbps data rate transmission [1], [2]. Optical vortex beams have been widely applied in communication systems, both in free space [4] and fiber [5], [6], because of the orbital angular momentum (OAM) carried [7]. THz vortex beams go beyond conventional THz waves, which will promisingly achieve ultrahigh data capacity and speed based on THz communication systems [8]. The transmission of the THz vortex beams in free space is affected by atmospheric turbulence. A fiber capable of stably transmitting the THz vortex beams is required. Research on the fiber for transmitting the THz vortex beams has emerged [9]–[11]. The ring radius of THz vortex beams is continually larger as the topological charge increases. Vortex beams with multiple topological charges will be a challenge to couple into a fixed-aperture fiber

Methods

Results

Conclusion