Lateral and transverse shifts in reflected dipole radiation

Abstract

In-plane (lateral) and out-of-plane (transverse) shifts in the direction of arbitrarily polarized electromagnetic waves in a denser medium, reflected totally or partially at an interface with a rarer medium, are calculated exactly, in terms of the deviation of the Poynting vector from radial. The shifts are analogous to the Goos-Hänchen and FedorovImbert shifts for beams. There is a transverse shift even for unreflected dipole radiation if the polarization is not linear. With reflection, there is a transverse shift for linear polarization, provided this is not pure transverse electric or transverse magnetic. The contributions from the geometrical ray, the lateral ray that interferes strongly with it, and the large peak at the Brewster angle (for transverse magnetic polarization), are calculated asymptotically far from the geometrical image. At the critical angle, the lowest order asymptotics is inadequate and a more sophisticated treatment is devised, reproducing the exact shifts accurately.

Goos–Hänchen and Imbert–Fedorov shifts: a novel perspective

“…Detailed theoretical derivations of both GH and IF shifts may be found in the current literature for surfaces of different types (dielectric, metallic, multilayered, etc), and for light beams of varying shapes (Hermite-Gauss, Laguerre-Gauss, Bessel, etc). The interested reader may consult [5][6][7][8] for early expositions and [9][10][11][12][13][14][15] for more accessible modern treatments of the subject. From these studies it emerges that, given a specific reflecting surface, beams of different shapes yield shifts of different extents.…”

Are Fresnel filtering and the angular Goos–Hänchen shift the same?

“…Confined within the plane of incidence and therefore comparable to the 2D fields in microcavities, are the spatial and angular Goos-Hänchen shift (GH) [7,8] and it is the latter which concerns us here as a related effect to FF. In its simplest form the angular GH shift pertains to generic incidence angles, that is not for the critical angle or the Brewster angle, although these special cases have been studied too [9,10,11]. Using the same simple picture as above, but for generic incidence (see Fig.…”

Highly nonparaxial spin Hall effect and its enhancement by plasmonic structures

“…Several experiments have confirmed the existence of the effect [5][6][7][8][9][10]. The simplest version of the effect is known as Federov-Imbert effect [11][12][13] and is seen prominently as a polarization dependent transverse shift on the reflected beam at a dielectric interface. The shift occurs relative to the prediction of geometrical optics.…”

“…The curves are normalized to the corresponding propagation length of the surface plasmons l = 1/Im(κ sp ) which can be derived from the poles of the reflection coefficient in Eq. (13). Obviously, the enhancement dies off for interatom distances d ≫ l which shows that the plasmonic enhancement is due to a excitation transition mediated by the surface plasmons.…”

“…We trace the existence of the effect to the fact that the dipole field is far from a paraxial field and in fact contains all the Fourier components including the evanescent waves. It has been shown that the image of a dipole in far field is displaced [13,29]. Further Maxwell equations imply that the vectorial properties of the fields change on propagation.…”