Optical vortex arrays, with their unique wavefront structures, find extensive applications in fields such as optical communications, trapping, imaging, metrology, and quantum. The methods used to generate these vortex beam arrays are crucial for their applications. In this review, we begin with introducing the fundamental concepts of optical vortex beams. Subsequently, we present three methods for generating them, including diffractive optical elements, metasurfaces, and integrated optical devices. We then explore the applications of optical vortex beam arrays in five different domains. Finally, we conclude with a summary and outlook for the research on optical vortex beam arrays.

In recent years, optical phased arrays (OPAs) have attracted great interest for their potential applications in light detection and ranging (LiDAR), free-space optical communications (FSOs), holography, and so on. Photonic integrated circuits (PICs) provide solutions for further reducing the size, weight, power, and cost of OPAs. In this paper, we review the recent development of photonic integrated OPAs. We summarize the typical architecture of the integrated OPAs and their performance. We analyze the key components of OPAs and evaluate the figure of merit for OPAs. Various applications in LiDAR, FSO, imaging, biomedical sensing, and specialized beam generation are introduced.

A pin-like beam is a kind of structured light with a special intensity distribution that can be against diffraction, which can be seen as a kind of quasi-nondiffracting beam (Q-NDB). Due to its wide applications, recently, numerous researchers have used optical lenses or on-chip integrated optical diffractive elements to generate this kind of beam. We theoretically verify and experimentally demonstrate an all-fiber solution to generate a subwavelength inverted pin beam by integrating a simple plasma structure on the fiber end surface. The output beams generated by two kinds of plasma structures, i.e., nanoring slot and nanopetal structure, are investigated and measured experimentally. The results show that both the structures are capable of generating subwavelength beams, and the beam generated using the nanopetal structure has the sidelobe suppression ability along the x-axis direction. Our all-fiber device can be flexibly inserted into liquid environments such as cell cultures, blood, and biological tissue fluids to illuminate or stimulate biological cells and molecules in them. It provides a promising fiber-integrated solution for exploring light–matter interaction with subwavelength resolution in the field of biological research.

Orbital angular momentum (OAM), described by an azimuthal phase term exp ( jlθ ) , has unbound orthogonal states with different topological charges l. Therefore, with the explosive growth of global communication capacity, especially for short-distance optical interconnects, light-carrying OAM has proved its great potential to improve transmission capacity and spectral efficiency in the space-division multiplexing system due to its orthogonality, security, and compatibility with other techniques. Meanwhile, 100-m free-space optical interconnects become an alternative solution for the “last mile” problem and provide interbuilding communication. We experimentally demonstrate a 260-m secure optical interconnect using OAM multiplexing and 16-ary quadrature amplitude modulation (16-QAM) signals. We study the beam wandering, power fluctuation, channel cross talk, bit-error-rate performance, and link security. Additionally, we also investigate the link performance for 1-to-9 multicasting at the range of 260 m. Considering that the power distribution may be affected by atmospheric turbulence, we introduce an offline feedback process to make it flexibly controllable.