From Multimode Nonlinear Optics to High-Dimensional Quantum Communications

Quantum photonics often relies on nonlinear optics for the generation of photons, followed by reconfigurable linear optical networks for coherent control. In this talk, I will review our study of multimode nonlinear optics in fibers [1,2], which also enabled our realization of an all-fiber entangled photon pairs source [3]. These photons are spatially entangled in the eigenmodes of the multimode fiber, allowing for high-dimensional quantum communications. I will then present a couple of methods to coherently control such states. The first is achieved by multiplane light conversion based on a spatial light modulator [4], while the second is by employing a “Fiber piano” [5]; a piezo-actuator array that deforms the multimode fiber. Finally, I will introduce a novel Quantum Key Distribution protocol that utilizes high-dimensional encoding to boost the secure key rate and its experimental implementation [6].

[1] Kfir Sulimany, et al. Physical Review Letters 121.13 (2018): 133902. 

[2] Kfir Sulimany, et al. Optica 9.11 (2022): 1260-1267. 

[3] Kfir Sulimany, and Yaron Bromberg. npj Quantum Information 8.1 (2022): 1-5. 

[4] Ohad Lib, Kfir Sulimany, and Yaron Bromberg. Physical Review Applied 18.1 (2022): 014063. 

[5] Finkelstein, Zohar, Kfir Sulimany, et al. APL Photonics 8, no. 3 (2023).

[6] Kfir Sulimany, et al. arXiv preprint arXiv:2105.04733 (2021). Under review.