Classical to quantum transfer of optical vortices
Abstract
We show that an optical vortex beam, implemented classically, can be transferred to the transverse amplitude of a heralded single photon. For this purpose we have relied on the process of spontaneous parametric downconversion (SPDC) for the generation of signal and idler photon pairs, using a pump in the form of a Bessel-Gauss (BG) beam with orbital angular momentum (specifically, with topological charge l = 1 and l = 2). We have designed our source so that it operates within the short SPDC crystal regime for which, the amplitude and phase of the pump may be transferred to a heralded single photon. In order to verify the vortex nature of our heralded single photon, we have shown that the conditional angular spectrum and the transverse intensity at the single-photon level match similar measurements carried out for the pump. In addition, we have shown that when our heralded single photon is diffracted through a triangular aperture, the far-field singlephoton transverse intensity exhibits the expected triangular arrangement of intensity lobes associated with the presence of orbital angular momentum.
Cite
@article{arxiv.1407.6407,
title = {Classical to quantum transfer of optical vortices},
author = {Veronica Vicuna-Hernandez and Hector Cruz-Ramirez and Roberto Ramirez-Alarcon and Alfred B. U'Ren},
journal= {arXiv preprint arXiv:1407.6407},
year = {2015}
}
Comments
Accepted for publication in Optics Express. 11 pages, 6 figures