Abstract
We report an experimental demonstration of effective entanglement in a prepare-and-measure type of quantum key distribution protocol. Coherent polarization states and heterodyne measurement to characterize the transmitted quantum states are used, thus enabling us to reconstruct directly their function. By evaluating the excess noise of the states, we experimentally demonstrate that they fulfill a nonseparability criterion previously presented by Rigas et al. [J. Rigas, O. Gühne, and N. Lütkenhaus, Phys. Rev. A 73, 012341 (2006)]. For a restricted eavesdropping scenario, we predict key rates using postselection of the heterodyne measurement results.
5 More- Received 14 March 2006
DOI:https://doi.org/10.1103/PhysRevA.74.042326
©2006 American Physical Society