Vortex beam: generation and detection of orbital angular momentum [Invited]

Recent advances in the research of vortex beams, structured beams carrying orbital angular momentum (OAM), have revolutionized the applications of light beams, such as advanced optical manipulations, high-capacity optical communications, and super-resolution imaging. Undoubtedly, the methods for generation of a vortex beam and detection of its OAM are of vital importance for the applications of vortex beams. In this review, we first introduce the fundamental concepts of vortex beams briefly and then summarize approaches to generating and detecting the vortex beams separately, from bulky diffractive elements to planar elements. Finally, we make a concise conclusion and outline that is yet to be explored.