The orbital angular momentum (OAM) of electromagnetic waves — a kind of “structured light” — is associated with a helical or twisted wavefront. The helical modes are characterized by a topological ...

Photons can have half-integer values of angular momentum when they are confined to fewer than three dimensions. That is the conclusion of physicists in Ireland, who have revived an experiment first ...

Optical vortex plays an important role in a variety of fields, such as particle tweezing, quantum communication, astrophysics, and microscopy. Especially, the application of optical vortex has been ...