Photon Source: Prepare-and-Measure for Quantum Communication

Abstract

Photon Source, Prepare-and-Measure for Quantum Communication. The present invention relates to a photon preparation system for quantum communication, the system comprising a polarized light source (210) and an optical emission head (211) including a telescope (213) emitting photons into a channel. The system further comprises a phase modulation system (205a-d) applied to photons produced by the source (210), as well as a first optical plate (202a, 204a, 204b) and a second optical plate (202b, 204c, 204d). The first optical plate (202a, 204a, 204b) separates photons along distinct optical paths, and the second plate (202b, 204c, 204d) recombines the photons from the optical paths that have undergone processing by the phase modulation system (205a-d).At the end of the path between the source (210) and the optical emission head (211), the phase modulation is adapted to each of the distinct paths (215a-215d) to control the polarization of the photons emitted in the channel for the purposes of quantum communication. Figure for the abstract: 2.