Cavity field spectra of two different atoms interacting with a two-mode field through Raman process

The cavity field spectra of two different atoms interacting with two-mode fields through Raman process are studied. The effects of relative coupling constant R = g(2)/g(1) on the spectrum structure are discussed. It is found that R plays a different role in the syectrum for vacuum, weak or strong initial field. Degenerate spectrum structure appears usually for R = 1 or R = 0. A complicated asymmetric multi-peak structure appears when R is between 0 and 1. When the field of upper frequency mode is vacuum, its spectrum is influenced sensitively by the field intensity of the other mode for fixed R.