Superradiance-assisted photonic Fock state generation and their quantum dynamics*

Photonic Fock states represent the foundational quantum states of radiation fields, enabling many applications, such as enhancing probing sensitivity in quantum metrology and efficient quantum simulations. To date, one principal scheme of generating the photonic Fock states is to use the cavity or circuit QED systems, e.g., by injecting single photons into a cavity containing a qubit, or by controlling the atom-cavity interactions. Although few-photon Fock states have been experimentally demonstrated, the capability of generating Fock states is fundamentally limited by the short decoherence times, and thus it has been challenging to generate Fock states with large photon numbers. Here, we present an alternatively appealing solid-state approach employing superradiant atoms within a chiral waveguide, enabling the deterministic generation of traveling multi-photon Fock states. As the proposed scheme does not involve photon-adding processes, the shortened radiative decay time in superradiance does not fundamentally limit the generation of the multi-photon Fock states. We provide explicit formulations for the resultant quantum photonic states and their associated correlation functions. Moreover, we show that the resultant output photonic states can be engineered to cross over between the Fock states and multi-photon bound states by controlling the initial Dicke states, which expands the potential applications to quantum nonlinear optics, e.g., correlated two-photon excitation microscopy.