Absorption spectrum of a resonantly driven degenerate V-type atom with a dc-field coupling between excited states
Institute of Theoretical Physics, Lanzhou University, Lanzhou, 730000, P.R. China
Corresponding author: a email@example.com
Revised: 13 December 2006
Published online: 31 January 2007
We study the absorption spectra of a degenerate V-type atom, where a resonant driving field and a probe field drive different branches of transitions and a dc field is applied to drive the transition between two excited states. The effects of vacuum induced coherence (VIC) on the absorption spectra are investigated. It is demonstrated that in some special cases the VIC can lead to the depression of absorption and narrow resonance. The origin of these features are discussed. When the pump field and the dc field have the same intensity, it is interesting to find that the whole absorption spectrum comes mainly from the absorptions induced by the interferences among different transitions between dressed states.
PACS: 42.50.Gy – Effects of atomic coherence on propagation, absorption, and amplification of light; electromagnetically induced transparency and absorption / 42.50.Hz – Strong-field excitation of optical transitions in quantum systems; multiphoton processes; dynamic Stark shift
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2007