Quantum operations on entangled photons using Lyot filters
David H. Hughes, Reinhard K. Erdmann, Vladimir Valer'evich Nikulin · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2016
Lyot filters have been designed for multi-access high capacity wavelength division multiplexing between a communications hub and spatially separated spokes. Reported here are modifications to a basic classical communications Lyot filter stage [1], but using a hyper-entangled bipartite input state possessing non-degenerate frequencies for advanced quantum communications. Lyot filters and pre-shared linking knowledge can be used to better ensure efficiency and efficacy in manifesting entanglement correlations between polarization degrees of freedom in non-rotationally invariant measurement bases. Lyot filters also allow entangled photon routing, a function of entanglement between incident frequencies and polarization.