Electromagnetically induced transparency (EIT) and electromagnetically induced absorption (EIA) resonances excited by a strong two-frequency field are considered for various values of the total angular momenta of the ground (F g ) and excited (F e ) states at a degenerated optical closed transition F g → F e . The light field is formed by two co-propagating waves with arbitrary elliptical polarisations. The process of spontaneous transfer of anisotropy from the excited state to the ground state is shown to determine the formation of the EIA resonance at the transition F g = F → F e = F + 1. The results obtained generalise the classification of transitions into 'bright' (F g = F → F e = F + 1) and 'dark' (F g = F → F e = F and F g = F → F e = F – 1) transitions with respect to the direction of a subnatural resonance.

中文翻译：

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椭圆偏振波光场中电磁感应的透明性和吸收共振

对于在简并光下的基态（F g）和激发态（F e）的总总角动量的各种值，考虑了由强双频场激发的电磁感应透明度（EIT）和电磁感应吸收（EIA）共振闭合过渡F g→F e。光场是由两个具有任意椭圆偏振的共传播波形成的。各向异性从激发态到基态的自发转移过程表明，确定了跃迁F g = F→F e = F + 1时EIA共振的形成。所得结果概括了跃迁的分类为'明亮（F g = F→F e = F + 1）和“黑暗”（F g = F→F e = F且F g = F→F e = F – 1）相对于a方向的过渡亚自然共鸣。