Coherence effects in mesoscopic higher harmonic multistability

The interaction of a mesoscopic system of coherently injected two-level Rydberg atoms with a coherently driven single cavity mode is treated outside the rotating wave approximation (RWA). The additional first harmonic component of the output field (outside RWA) exhibits closed hysteresis loops and multiple-switching processes, compared with the hysteresis cycles for the nonoscillatory (fundamental) component within the RWA. This is achieved via two controls: (i) varying the coherent population excitation and relative phase parameters (θ, φ) of the coherently injected atoms, and, (ii) varying simultaneously atom and cavity detuning parameters.