Quantum orbital angular momentum of elliptically symmetric light

Abstract

We present a quantum mechanical analysis of the orbital angular momentum of a class of recently discovered elliptically-symmetric stable light fields -the so-called Ince-Gauss modes. We study, in a fully quantum formalism, how the orbital angular momentum of these beams varies with their ellipticity and discover several compelling features, including: non-monotonic behavior, stable beams with real continuous (non-integer) orbital angular momenta, and orthogonal modes with the same orbital angular momenta. We explore, and explain in detail, the reasons for this behavior. These features may have application to quantum key distribution, atom trapping, and quantum informatics in general -as the ellipticity opens up a new way of navigating the photonic Hilbert space.

Normal modes and mode transformation of pure electron vortex beams

“…Index p has so far featured little in both experimental and theoretical analyses of vortex beams that seemed to have concentrated primarily on the cases where p = 0, in which the modes are called doughnut modes. This has led some to refer to the p index as the forgotten quantum number in optical vortex beam physics [34]. Similarly, the radial structure has not yet featured much in research on electron vortex beams [35].…”

Role of cavity degeneracy for high-order mode excitation in end-pumped solid-state lasers

“…For instance, high-order helical beams are found to possess orbital angular momentum [1], Bessel beams [2] have very low diverging properties, and Airy beams are freely accelerating [3]. Such transverse structures departing from the fundamental Gaussian mode are interesting for applications such as optical tweezers and microscopy [4], particle trapping [5], or quantum information [6]. While the usual way of tailoring beams is to inject a fundamental Gaussian mode in some extra-cavity optical elements, such as phase plates, axicons, or spatial light modulators, direct high-order mode laser oscillation would certainly lead to better quality beams with a greater efficiency.…”

Phenomenology of complex structured light in turbulent air

“…In this case, the indices of states LG n, and IG p,m, are related as: | | = m and n = (p − m)/2. Additionally, when the elliptic coordinates tend to the cartesian coordinates, namely → ∞, the IG modes will be transferred into helical Hermite-Gaussian (HG) modes [49,51,52]. In this case, the indices of modes HG nx,ny and IG p,m, are related as: n x = m and n y = (p − m).…”