Bouchard, FrédéricHeshami, KhabatEngland, DuncanFickler, RobertBoyd, R. W.Englert, Berthold-GeorgSánchez Soto, Luis LorenzoKarimi, E.2023-06-172023-06-172018-12-042521-327X10.22331/q-2018-12-04-111https://hdl.handle.net/20.500.14352/13167© Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften. All authors would like to thank Gerd Leuchs, Markus Grassl and Imran Khan for helpful discussions. F.B. acknowledges the financial support of the Vanier graduate scholarship of the NSERC. R.F. acknowledges the financial support of the Banting postdoctoral fellowship of the NSERC. This work was supported by Canada Research Chairs; Canada Foundation for Innovation (CFI); Canada Excellence Research Chairs, Government of Canada (CERC); Canada First Research Excellence Fund (CFREF); Natural Sciences and Engineering Research Council of Canada (NSERC); Singapore Ministry of Education (partly through the Academic Research Fund Tier 3 MOE2012-T3-1-009)and the National Research Foundation of Singapore; and Spanish Ministerio de Economia y Competitividad (MINECO).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.engjournal articlehttps://doi.org/10.22331/q-2018-12-04-111https://quantum-journal.orgopen access535Orbital angular-MomentumCryptographyLightEntanglementSecurityDynamicsStatesWalkÓptica (Física)2209.19 Óptica Física