Related papers: Paraxial Light Beams with Angular Momentum
Circular-Beams were introduced as a very general solution of the paraxial wave equation carrying Orbital Angular Momentum. Here we study their properties, by looking at their normalization and their expansion in terms of Laguerre-Gauss…
It is well-known that electric spin angular momentum and electric orbital angular momentum are conserved under paraxial propagation of travelling waves in free-space. Here we study the electric and magnetic angular momentum in…
The orbital angular momentum (OAM) of light and optical vortices are closely related concepts that are often conflated. The conserved OAM arises fundamentally from the SO(3) rotational symmetry of spacetime, while the concept of vortices…
The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam…
Light beam with optical vortices can propagate in free space only with integer orbital angular momentum. Here, we invert this scientific consensus theoretically and experimentally by proposing light beams carrying natural non-integer…
In light beams with circular or elliptic polarization, the transverse energy flow consists of the "spin" and "orbital" parts. Both of them can induce the orbital motion of microparticles suspended within the field of a light beam, and this…
We examine several retro-reflecting optical elements, each involving two reflections. In the case of a hollow metallic cone having an apex angle of 90\degree, a circularly-polarized incident beam acquires, upon reflection, the opposite spin…
We study the interaction of a light beams carrying angular momentum with a single, trapped and well localized ion. We provide a detailed calculation of selection rules and excitation probabilities for quadrupole transitions. The results…
In this letter a general method for expanding paraxial beams into multipolar electromagnetic fields is presented. This method is applied to the expansion of paraxial modes with orbital angular momentum (OAM), showing how the paraxial OAM is…
We demonstrate that the orbital angular momentum flux density of a paraxial light beam can change on propagation in free space. These changes are entirely due to the spatial coherence state of the source, and the effect is analogous to…
There is recent interest in the use of light beams carrying orbital angular momentum (OAM) for creating multiple channels within free-space optical communication systems. One limiting issue is that, for a given beam size at the transmitter,…
We study theoretically the exchange of angular momentum between a photon beam and a plasma vortex, and demonstrate the possible excitation of photon angular momentum states in a plasma. This can be relevant to laboratory and space plasma…
Optical beams with a new and distinctive type of helicity have become the subject of much recent interest. While circularly polarised light comprises photons with spin angular momentum, these optically engineered 'twisted beams' (optical…
It is shown that the momentum density of free electromagnetic field splits into two parts. One has no contribution to the net momentum due to the transversality condition. The other yields all the momentum. The angular momentum that…
It has been known for a long time that light carries both linear and angular momenta parallel to the direction of propagation. However, only recently it has been pointed out that beams of light, under certain conditions, may exhibit a…
Orbital angular momentum is an important concept in optics, thus numerous researches explore the principles and applications of light beams with orbital angular momentum. This type of light beam is also called vortex beam, whose inherent…
We investigate in detail the focusing of a circularly polarized Laguerre-Gaussian laser beam ($\hbar \ell$ orbital angular momentum per photon; $\sigma=1/-1$ for left/right-handed polarization) by a high numerical aperture objective. The…
We theoretically analyze and experimentally measure the extrinsic angular momentum contribution of topologically structured darkness found within fractional vortex beams, and show that this structured darkness can be explained by evanescent…
The spin angular momentum in an elliptically polarized beam of light plays several noteworthy roles in optical traps. It contributes to the linear momentum density in a non-uniform beam, and thus to the radiation pressure exerted on…
Optical intrinsic angular momentum can be regarded as derivation from spatial superposition of optical vector fields embodied by spinning or and spiraling the electric field vector. We employ vectorial formulation derivation to…