Vortex states of photons, electrons, and other particles are non-plane-wave solutions of the
corresponding wave equation with helicoidal wave fronts. These states possess an intrinsic …

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 …

The recent prediction and subsequent creation of electron vortex beams in a number of
laboratories occurred after almost 20 years had elapsed since the recognition of the physical …

In the past decade, optical orbital angular momentum (OAM) has entered the field of
plasmonics in the form of surface-confined vortices, generating vast interest. Here we give …

The optical vortex on a chip is of extreme importance for many applications in nanoscience,
and as well-known, the chiral metallic nanostructures like plasmonic vortex lenses (PVLs) …

Zero-order and higher-order Bessel beams are well-known nondiffracting beams. Namely,
they propagate with invariant profile (intensity) and carry a fixed orbital angular momentum …

Free electron beams that carry high values of orbital angular momentum (OAM) possess
large magnetic moments along the propagation direction. This makes them an ideal probe …

Electron vortex beams carrying intrinsic orbital angular momentum (OAM) are produced in
electron microscopes where they are controlled and focused by using magnetic lenses. We …

A general orbital-angular-momentum (OAM) mode selection principle is put forward
involving the rotationally symmetric superposition of chiral states. This principle is not only …

Electron diffraction gratings can be used to imprint well-defined phase structure onto an
electron beam. For example, diffraction gratings have been used to prepare electron beams …