BACKGROUND Optical vortices provide one of the promising solutions for enhancing the
capacity of data multiplexing to meet an unprecedented growth in big data and internet traffic …

Optical vortices (OVs) carrying orbital angular momentum (OAM) have attracted
considerable interest in the field of optics and photonics owing to their peculiar optical …

Geometric-phase metasurfaces, recently utilized for controlling wavefronts of circular
polarized (CP) electromagnetic waves, are drastically limited to the cross-polarization …

Vortex beam carrying orbital angular momentum (OAM) has been widely explored in optical
and microwave regions attributed to its potential characteristics in communication systems …

Secure packaging and transportation of light-sensitive chemical and biomedical test tubes
are crucial for environmental protection and public health. Benefiting from the compact form …

Metasurfaces are ultrathin metamaterials consisting of planar electromagnetic (EM)
microstructures (eg, meta-atoms) with pre-determined EM responses arranged in specific …

Metasurfaces, two-dimensional equivalents of metamaterials, are engineered surfaces
consisting of deep subwavelength features that have full control of the electromagnetic …

In this Letter, we demonstrate highly efficient, polarization-insensitive planar lenses
(metalenses) at red, green, and blue wavelengths (λ= 660, 532, and 405 nm). Metalenses …

Metamaterials have great capabilities and flexibilities in controlling electromagnetic (EM)
waves because their subwavelength meta-atoms can be designed and tailored in desired …

This article reviews recent progress leading to the generation of optical vortex beams. After
introducing the basics of optical vortex beams and their promising applications, we …