Experimental investigation of high-dimensional quantum key distribution protocols with twisted photons

Frédéric Bouchard1, Khabat Heshami2, Duncan England2, Robert Fickler1, Robert W. Boyd1,3,4, Berthold-Georg Englert5,6,7, Luis L. Sánchez-Soto3,8, and Ebrahim Karimi1,3,9

1Department of physics, University of Ottawa, Advanced Research Complex, 25 Templeton, Ottawa ON Canada, K1N 6N5
2National Research Council of Canada, 100 Sussex Drive, Ottawa ON Canada, K1A 0R6
3Max-Planck-Institut für die Physik des Lichts, Staudtstraße 2, 91058 Erlangen, Germany
4Institute of Optics, University of Rochester, Rochester, NY 14627, USA
5Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore
6Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
7MajuLab, CNRS-UNS-NUS-NTU International Joint Unit, UMI 3654, Singapore.
8Departamento de Óptica, Facultad de Física, Universidad Complutense, 28040 Madrid, Spain
9Department of Physics, Institute for Advanced Studies in Basic Sciences, 45137-66731 Zanjan, Iran.

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Abstract

Quantum key distribution is on the verge of real world applications, where perfectly secure information can be distributed among multiple parties. Several quantum cryptographic protocols have been theoretically proposed and independently realized in different experimental conditions. Here, we develop an experimental platform based on high-dimensional orbital angular momentum states of single photons that enables implementation of multiple quantum key distribution protocols with a single experimental apparatus. Our versatile approach allows us to experimentally survey different classes of quantum key distribution techniques, such as the 1984 Bennett & Brassard (BB84), tomographic protocols including the six-state and the Singapore protocol, and to investigate, for the first time, a recently introduced differential phase shift (Chau15) protocol using twisted photons. This enables us to experimentally compare the performance of these techniques and discuss their benefits and deficiencies in terms of noise tolerance in different dimensions.

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