Speaker: Prof. Kejie Fang, University of Illinois at Urbana-Champaign
Abstract: Interaction between individual photons forms the foundation of gate-based optical quantum computing among other quantum-enabled technologies. Quantum emitter-mediated photon interactions are fundamentally constrained by stringent operation conditions and the available photon wavelength and bandwidth, posing difficulty in upscaling and practical applications. It is a long-standing goal to realize interactions between individual photons using the more engineerable bulk optical nonlinearity, such as chi2 and chi3. I will describe the first observation of photon-photon interaction mediated by a virtual photon in an integrated photonic circuit with a substantial chi2 nonlinearity and the resulting quantum correlations of transported photons including photon repulsion and attraction. These results represent a significant leap in nonlinear optics and quantum photonics, transcending the longtime paradigm of parametric nonlinear processes and paving the way towards strongly interacting photons in bulk nonlinear systems. Moreover, I will talk about using such integrated photonic platform with extreme nonlinearity for nonlinearity-enabled quantum network protocols.