title: High-directional vortex beam emitter based on Archimedean spiral adiabatic waveguides.
abstract: Integrated devices that emit light beams with orbital angular momentum (OAM) are becoming key components for wide-ranging applications. Here we propose and demonstrate a highly directional silicon photonic vortex beam emitter based on a 3-turn Archimedean spiral adiabatic waveguide integrated with an angular grating. Such a compact emitter is capable of generating vortex beams with small divergence angles and high directivity. Various orders of OAM modes can be selectively generated by the emitter at different wavelengths with a side-mode suppression ratio as large as 13.6 dB.
authors.forename: Shimao
authors.initials: S
authors.lastname: Li
authors.forename: Wen
authors.initials: W
authors.lastname: Yu
authors.forename: Laura
authors.initials: L
authors.lastname: Meriggi
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Xiao
authors.forename: Zhichao
authors.initials: Z
authors.lastname: Nong
authors.forename: Xinlun
authors.initials: X
authors.lastname: Cai
authors.forename: Marc
authors.initials: M
authors.lastname: Sorel
authors.forename: Siyuan
authors.initials: S
authors.lastname: Yu