Manipulating counter-rotating interactions in the quantum Rabi model via qubit frequency modulation

Understand

We propose a practical approach to manipulate the counter-rotating (CR) interactions in the quantum Rabi model by introducing a sinusoidal modulation to the transition frequency of the quantum two-level system in this model.

• By choosing appropriate modulation frequency and amplitude, enhancement and suppression of the CR interactions can be achieved in the Jaynes-Cummings regime (including both weak- and strong-coupling cases) as well as the ultrastrong-coupling regime.
• In particular, we calculate the output photon emission of the cavity vacuum state under enhanced CR terms.
• Our results show that continuous and steady photon emission from the cavity vacuum can be observed in the Jaynes-Cummings regime as a consequence of this enhancement.