Measurements of transverse lateral and longitudinal angular shifts of high-azimuthal-mode Laguerre–Gaussian beams reflected at a dielectric interface near critical incidence

Abstract

Laguerre–Gaussian (LG) beams with a radial mode index p = 0 and azimuthal mode indices l from −5 to 5 are reflected at a glass–air interface near critical incidence, and the transverse lateral and longitudinal angular shifts of the intensity center of gravity are measured relative to the LGp=0,l=0 beam. The LG beams are generated with a programmable spatial light modulator that displays computer-generated holograms encoding phase and amplitude information. The measured relative shifts are greatly enhanced near the critical angle and agree with the theoretical values numerically calculated using the wavenumber-space representation.