Guided-wave optics for real quantum relay applications
Résumé
Periodically poled lithium niobate waveguides (PPLN/W) are considered to be one of the most useful toolboxes for quantum communication experiments. Thanks to the high optical confinement over longer lengths than in bulk configurations (a few cm in our case), such structures provide highly efficient non-linear interactions, both in down- and up-conversion regimes. Within the framework of long-distance quantum communication at telecom wavelengths, PPLN/Ws have therefore been proved to be a key ingredient for building ultra-bright sources of energy-time, time-bin, as well as polarization entangled pairs of photons, up-conversion based detectors for telecom photon detection, photonic quantum interfaces for coherent wavelength conversion, and also for quantum relays in the entanglement swapping configuration.