A tunable entanglement distiller for arbitrary two-photon polarization qubits is demonstrated using novel tunable local filters constructed with rotatable birefringent prisms. The distillation is confirmed by comparing the concurrences of the two-photon states.
We experimentally demonstrate optimal entanglement distillation from two forms of two-qubit mixed states under local filtering operations according to the constructive method introduced by [F. Verstraete, Phys. Rev. A 64, 010101(R) (2001)10.1103/PhysRevA.64.010101]. In principle, our setup can be easily applied to distilling entanglement from arbitrary two-qubit partially mixed states. We also test the violation of the Clauser-Horne-Shinmony-Holt inequality for the distilled state from the first form of mixed state to show its "hidden nonlocality."
An entanglement distillation scheme is proposed for an amplitude-damped polarization-entangled photon states via local filtering operations. The local filtering operations, i.e. positive operator-valued measure, on photons are realized by a series of Brewster window pairs. The entanglement of the survived photon pairs in the scheme will be much larger than that of the initial ones. In this sense, this distillation scheme is better than the currently existing entanglement protection scheme, where only the entanglement decaying time is prolonged and the entanglement is not enhanced at all. In addition, this scheme is simple and feasible within the current linear optical techniques.
We experimentally demonstrate optimal entanglement distillation from two forms of two-qubit mixed states under local filtering operations according to the constructive method intruduced by F. Verstraete et al. [Phys. Rev. A 64, 010101(R) (2001)]. In principle, our set-up can be easily applied to distilling entanglement from arbitrary two-qubit partially mixed states. We also test the violation of the Clauser-Horne-Shinmony-Holt(CHSH) inequality for the distilled state from the first form of mixed state to show its "hidden non-locality".
Future quantum networks offer the potential for new communication and computation applications. These quantum networks will undoubtedly require the routing of quantum information between distant parties. In order to reliably achieve the transmission of entangled states over such a network, some entanglement distillation protocol can be implemented on an ensemble of entangled photon pairs. Here, we demonstrate such a protocol by recovering quantum information using local filters on each photon of a polarization-entangled state in the presence of a common source of decoherence in the telecom fiber infrastructure, polarization mode dispersion (PMD).