Probe gain via four-wave mixing based on spontaneously generated coherence
Yang Hong1, Zhang Ting-gui2, Zhang Yan3,
       

(color online) Probe gain spectra (imaginary parts of probe susceptibilities) as functions of probe detuning with various θ. The relative parameters are , MHz, , , . MHz, MHz, and . The inset without considering SGC ( ) is the same as the line of in the main part.