Temporal trapping: a route to strong coupling and deterministic optical quantum computation

The realization of deterministic photon-photon gates is a central goal in optical quantum computation and engineering. A longstanding challenge that nonlinearities scalable, room-temperature material platforms are too weak to achieve the required strong coupling, due critical loss-confinement tradeoff existing photonic structures. In this work, we introduce novel confinement method, dispersion-engineered temporal trapping, circumvent tradeoff, paving route all-optical coupling. Temporal imposed by an auxiliary trap pulse via cross-phase modulation, which, combined with spatial waveguide, creates "flying cavity" enhances nonlinear interaction strength at least order magnitude. Numerical simulations confirm trapping confines multimode dynamics single-mode subspace, enabling high-fidelity gate operations. With realistic dispersion engineering loss figures, show temporally trapped ultrashort pulses could coupling on near-term nanophotonic platforms. Our results highlight potential ultrafast optics become first high-bandwidth, platform achieves opening new path computing, simulation, light sources.