2015/12/07 by Nestor Bareza, Bareza, Nestor D., Nathaniel Hermosa +1
Engineering · Physics and Astronomy · #FOS: Physical sciences #Near-Field Optical Microscopy #Optics (physics.optics) #Orbital Angular Momentum in Optics #Plasmonic and Surface Plasmon Research
paper · pdf · doi:10.48550/arxiv.1512.01971
openalex publication_date 2015/12/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report a consequence of the orbital angular momentum (OAM) of a beam to its group velocity. We calculate the group velocity vg of Laguerre-Gauss beam (LG) with ℓ and at p=0. The vg reduction of LG beam even in free space is observed to have dependence on both orbital or winding number ℓ and the beam's divergence θ0. We found that light possessing higher ℓ travels relatively slower than that with lower ℓ values. This suggests that light of different OAM separate in the temporal domain along propagation and it is an added effect to the dispersion due to field confinement. Our results are useful for treating information embedded in light with OAM from astronomical sources and/or data transmission in free space.