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arXiv · 1502.06773

Orbital Angular Momentum (OAM) Vertical-Cavity Surface-Emitting Lasers

Huanlu Li·David Phillips·Xuyang Wang·Daniel Ho·Lifeng Chen·Xiaoqi Zhou·Jiangbo Zhu·Siyuan Yu·Xinlun Cai
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Abstract

Harnessing the Orbital Angular Momentum (OAM) of light is an appealing approach to developing photonic technologies for future applications in optical communications and high- dimensional Quantum Key Distributions (QKD). An outstanding challenge to the widespread uptake of the OAM resource is its efficient generation. We design a new device which can directly emit an OAM-carrying light beam. By fabricating micro-scale Spiral Phase Plates (SPPs) within the aperture of a Vertical-Cavity Surface-Emitting Laser (VCSELs), the linearly polarized Gaussian beam emitted by the VCSEL is converted into a beam carrying specific OAM modes and their superposition states with high efficiency and high beam quality. The innovative OAM emitter opens a new horizon in the field of OAM-based optical and quantum communications, especially for short reach data interconnects and Quantum Key Distribution (QKD).

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Huanlu Li, David Phillips, Xuyang Wang, Daniel Ho, Lifeng Chen, Xiaoqi Zhou, Jiangbo Zhu, Siyuan Yu, Xinlun Cai. 2015-02-24. Orbital Angular Momentum (OAM) Vertical-Cavity Surface-Emitting Lasers. https://arxiv.org/abs/1502.06773

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