2021/09/07 by Gustavo Cañas, Esteban S. Gómez, Cañas, G. +7
Engineering · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Optics (physics.optics) #Orbital Angular Momentum in Optics #Photonic Crystal and Fiber Optics #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.2109.03064
openalex publication_date 2021/09/07 · openalex created_date 2021/09/13 · openalex updated_date 2026/07/28
The capacity of optical communication channels can be increased by space division multiplexing in structured optical fibers. Radial core optical fibers allows for the propagation of twisted light--eigenmodes of orbital angular momentum, which have attracted considerable attention for high-dimensional quantum information. Here we study the generation of entangled photons that are tailor-made for coupling into ring core optical fibers. We show that the coupling of photon pairs produced by parametric down-conversion can be increased by close to a factor of three by pumping the non-linear crystal with a perfect vortex mode with orbital angular momentum ℓ, rather than a gaussian mode. Moreover, the two-photon orbital angular momentum spectrum has a nearly constant shape. This provides an interesting scenario for quantum state engineering, as pumping the crystal with a superposition of perfect vortex modes can be used in conjunction with the mode filtering properties of the ring core fiber to produce simple and interesting quantum states.