Abstract: Quantum teleportation and entanglement swapping utilize a linear optical Bell state measurement to herald successful operations. However, linear elements constrain the system by requiring indistinguishable photons and thus are vulnerable to multi-photon errors. Here we demonstrate a nonlinear Bell state analyzer utilizing the high nonlinearity of our indium gallium phosphide platform in a nanophotonic resonator. The efficient sum-frequency generation process allows spectrally distinguishable inputs and filters multi-photon events. We demonstrate performance down to the single-photon level and achieve fidelities more than 94 %. Our result demonstrates faithful quantum information protocols with spectrally distinguishable photons and no fundamental limit of fidelity.
Bio: Josh Akin is a 4th year ECE Ph.D. student in Kejie Fang’s group researching nonlinear quantum optics and information processing.