We theoretically study the electromagnetic field controlled photon correlation and radiation properties in a two-atom-cavity quantum electrodynamic (QED) system with different atom-cavity coupling strengths. When two three-level atoms are coherently driven by a probe field and a strong control field, forming a ladder type electromagnetically induced transparency configuration, there exist four different excitation pathways via the two photon processes, yielding four different frequencies for realizing two photon blockades. Carefully choosing the intensity of the control field, resonant single-photon and two-photon excitation can be achieved at the same probe field frequency. Thus, two photon blockade phenomenon can be significantly improved and the collective radiation behavior becomes superradiance or even hyperradiance. Our system presented here can be considered to be a converter of a weak coherent light to two correlated photons.

中文翻译：

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电磁场诱导具有高辐射行为的强双光子阻滞

我们从理论上研究了具有不同原子-腔耦合强度的双原子-腔量子电动力学 (QED) 系统中电磁场控制的光子相关性和辐射特性。当两个三级原子被一个探测场和一个强控制场相干驱动，形成梯形电磁感应透明构型时，通过两个光子过程存在四种不同的激发路径，产生四种不同的频率，实现两个光子的阻滞。仔细选择控制场的强度，可以在相同的探测场频率下实现共振单光子和双光子激发。因此，可以显着改善双光子阻塞现象，并且集体辐射行为变为超辐射甚至超辐射。