First-Order Quantum Phase Transition for Dicke Model Induced by Atom-Atom Interaction

Zhao Xiu-Qin^{1, 2}, Liu Ni^{1, †}, Liang Jiu-Qing¹

(Color online) Variations of the average photon number n_pq (a) (the solid line), the atomic population imbalance (b) (shte dashed line), and the average energy (c) (the dotted line) with respect to the atom-field coupling constant for the given parameter (the black line), 0.05 (the red line), 0.10 (the green line).