Deterministic qubit transfer between orbital and spin angular momentum of single photons.

In this work we experimentally implement a deterministic transfer of a generic qubit initially encoded in the orbital angular momentum of a single-photon to its polarization. Such a transfer of quantum information, which is completely reversible, has been implemented adopting an electrically tunable q-plate device and a Sagnac interferometer with a Dove prism. The adopted scheme exhibits high fidelity and low losses.