Comparison of absorption–dispersion and optical bistability behaviors between open and closed four-level tripod atomic systems
Karimi R., Asadpour S. H.†, Batebi S., Rahimpour Soleimani H.
       
(a) A four-level atomic system in a tripod-type configuration. (b) Unidirectional ring cavity with an atomic sample of length L . and are the incident and transmitted fields, respectively. Here, E c is the coherent control field.