Enhancing atom-field interaction in the reduced multiphoton Tavis-Cummings model

We propose a scheme to enhance the light-matter coupling in a cavity QED system where two A atoms are weakly coupled to a single-mode cavity via multiphoton interaction. By introducing a second-order nonlinear (parametric) driving of the cavity, the original N-photon exchanges between the atoms, and the cavity can be reduced to either an effective single- or two-photon transition depending on the odevity of N, with the effective atom-field interaction strength being significantly enhanced. This results in an N-dependent effective coupling strength on top of the exponential enhancement induced only by the parametric driving. As an example, we demonstrate that our proposal can be exploited for the preparation of high-fidelity steady-state entanglement. The proposed scheme could provide a feasible alternative for diverse applications in quantum technologies.