Multiphoton resonance and chiral transport in the generalized Rabi model

The generalized Rabi model (gRM) with both one-photon and two-photon coupling terms has been successfully implemented in circuit quantum electrodynamics systems. In this work, we examine theoretically multiphoton resonances in the gRM and derive their effective Hamiltonians. With different detunings in the system, we show that all three- to six-photon resonances can be achieved by involving two intermediate states. Furthermore, we study the interplay between multiphoton resonance and chiral transport of photon Fock states in a resonator junction with broken time-reversal symmetry. Depending on the qubit-photon interaction and photon-hopping amplitude, we find that the system can demonstrate different short-time dynamics.