“…In our numerical simulation, we take the cavity decay rate = 2 × 160 kHz, which has been realized in recent experiment of superradiance for 87 Sr clock transition [62], the atomic spontaneous decay rate = 2 × 7.5 kHz for the long-lived excited state of 3 1 , the weak cavity driven strength / = 0.1, and the single atom-cavity coupling / = 4, for which coupling strength on a forbidden transition has demonstrated capability in current experiments for single atoms trapped in the cavity with the quantization length of the cavity around a few millimeters [15,63]. Therefore, the free parameters in our system are reduced to cavity-light detuning Δ , Rabi frequency of the control field Ω, and optical Stark shift 0 by continuously tuning the sign and strength of Zeeman splitting ℏΔ in experiment [63]. Limited by the validity of our model, the numerical results presented below exhibit the parameter space 0 ≤ 0 / ≤ 4, corresponding the tunable magnetic field around a few tens of Gauss.…”