We report an experimental implementation of tripartite controlled quantum teleportation on quantum optical devices. The protocol is performed through bi- and tripartite entangled channels of discrete variables and qubits encoded in the polarization of individual photons. The experimental results demonstrate successful controlled quantum teleportation with a fidelity around 83%, well above the classical limit. By realizing the controlled quantum teleportation through a biseparable state, we show that tripartite entanglement is not a necessary resource for controlled quantum teleportation, and the controller's capability to allow or prohibit the teleportation cannot be considered to be a manifestation of tripartite entanglement. These results open new possibilities for further application of controlled quantum teleportation by lowering the teleportation channel's requirements.

Institute of Physics of the Czech Academy of Sciences Joint Laboratory of Optics of Palacký University and Institute of Physics of CAS 17 listopadu 50A 772 07 Olomouc Czech Republic

Institute of Physics University of Zielona Góra Z Szafrana 4a 65 516 Zielona Góra Poland

RCPTM Joint Laboratory of Optics of Palacký University and Institute of Physics of CAS Faculty of Science Palacký University 17 listopadu 12 771 46 Olomouc Czech Republic

References provided by Crossref.org

Enhancing collective entanglement witnesses through correlation with state purity