Related papers: Transition radiation from electrons with orbital a…
Besides a linear momentum, optical fields carry an angular momentum (AM), which have two intrinsic components: one is spin angular momentum (SAM) related to the polarization state of the field, and the other is orbital angular momentum…
Vortex $\gamma$ photons with intrinsic orbital angular momenta (OAM) possess a wealth of applications in various fields, e.g.-strong-laser physics, nuclear physics, particle physics and astrophysics-yet their generation remains unsettled.…
We theoretically study the generation of orbital angular momentum(OAM) based on four-wave mixing (FWM) process in a diamond-type inhomogeneously broadened $^{85}$Rb atomic system. We use density matrix formalism at weak probe limit to…
We calculate the transition radiation process $\nu \to \nu \gamma$ at an interface of magnetic field and vacuum. The neutrinos are taken to be with only standard-model couplings. The magnetic field fulfills the dual purpose of inducing an…
We perform a quantum theoretical calculation of transition radiation by neutral particles with spin 1/2 equipped with magnetic moments and/or electric dipole moments. The limit of vanishing masses is treated exactly for arbitrary refraction…
Based on a recent claim [Phys. Rev. Lett. 116, 127203 (2016)] that electron vortex can be used to image magnetism at the nanoscale in elastic scattering experiments, using transmission electron microscopy, a comprehensive computational…
Vortices are whirling disturbances commonly found in nature ranging from tremendously small scales in Bose-Einstein condensates to cosmologically colossal scales in spiral galaxies. An optical vortex, generally associated with a spiral…
The transition probability for the emission of a Bessel photon by an atomic system is calculated within first order perturbation theory. We derive a closed expression for the electromagnetic potentials beyond the paraxial approximation that…
We develop a free-carrier theory of the optical absorption of light carrying orbital angular momentum (twisted light) by bulk semiconductors. We obtain the optical transition matrix elements for Bessel-mode twisted light and use them to…
We investigate twisted electrons with a well defined orbital angular momentum, which have been ionised via a strong laser field. By formulating a new variant of the well-known strong field approximation, we are able to derive conservation…
We demonstrate the coherent transfer of the orbital angular momentum of a photon to an atom in quantized units of hbar, using a 2-photon stimulated Raman process with Laguerre-Gaussian beams to generate an atomic vortex state in a…
Light endowed with orbital angular momentum, commonly termed optical vortex light, has an azimuthal phase indexed by the orbital quantum number $l$. In contrast to the two basis states of the optical spin angular momentum, the interest in…
We consider the propagation of slow light with an orbital angular momentum (OAM) in a moving atomic medium. We have derived a general equation of motion and applied it in analysing propagation of slow light with an OAM in a rotating medium,…
Light beams with orbital angular momentum (OAM) are convenient carriers of quantum information. They can be also used for imparting rotational motion to particles and provide high resolution in imaging. Due to the conservation of OAM in…
Orbital angular momentum (OAM) of graphene electrons in a perpendicular magnetic field is calculated and corresponding magnetic moment is used to investigate the magnetism of perfect graphene. Variation in magnetization demonstrates its…
Thanks to progress in optics in the past two decades, it is possible to create photons carrying well-defined non-zero orbital angular momentum (OAM). Boosting these photons into high-energy range preserving their OAM seems feasible.…
A possibility of a few MeV electron beam diagnostics (Lorentz factor ~ 10) using polarization characteristics of the optical transition radiation (OTR) have been considered. Determinaton of the electron beam divergence have been performed…
A fundamental requirement for quantum technologies is the ability to coherently control the interaction between electrons and photons. However, in many scenarios involving the interaction between light and matter, the exchange of linear or…
We consider in a quantum field theory framework the effects of a classical magnetic field on the spin and orbital angular momentum (OAM) of a free electron. We derive formulae for the changes in the spin and OAM due to the introduction of a…
We study here fractional orbital angular momentum (OAM) states in electron vortex beams (EVB) from the perspective of geometric phase. We have considered the skyrmionic model of an electron, where it is depicted as a scalar electron…