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arXiv · 1404.7573

Real-time imaging of spin-to-orbital angular momentum quantum state teleportation

Manuel Erhard·Hammam Qassim·Harjaspreet Mand·Ebrahim Karimi·Robert W Boyd
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Abstract

Quantum teleportation is a process in which an unknown quantum state is transferred between two spatially separated subspaces of a bipartite quantum system which share an entangled state and communicate classically. In the case of photonic states, this process is probabilistic due to the impossibility of performing a two-particle complete Bell state analysis with linear optics. In order to achieve a deterministic teleportation scheme, harnessing other degrees of freedom of a single particle, rather than a third particle, has been proposed. Indeed, this leads to a novel type of deterministic teleportation scheme, the so-called hybrid teleportation. Here we report the first realization of photonic hybrid quantum teleportation from spin-to-orbital angular momentum degrees of freedom. In our scheme, the polarization state of photon A is transferred to orbital angular momentum of photon B. The teleported states are visualized in real-time by means of an intensified CCD camera. The quality of teleported states is verified by performing quantum state tomography, which confirms an average fidelity higher than 99.4%. We believe this experiment paves the route towards a novel way of quantum communication in which encryption and decryption are carried out in naturally different Hilbert spaces, and therefore may provide means of enhancing security.

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Manuel Erhard, Hammam Qassim, Harjaspreet Mand, Ebrahim Karimi, Robert W Boyd. 2014-04-30. Real-time imaging of spin-to-orbital angular momentum quantum state teleportation. https://doi.org/10.1103/physreva.92.022321

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