Study of width and height of EIT resonance in a Doppler broadened five-level system with varying probe power
Department of Physics, University of Calcutta, 92 A. P. C. Road, Kolkata, 700009, India
2 Jadavpur University, 188 Raja S. C. Mallik Road, Kolkata, 700032, India
Revised: 27 October 2008
Published online: 26 March 2009
We report the experimental observation of electromagnetically induced transparency (EIT) in a Doppler broadened rubidium vapour at room temperature for different probe intensities at a fixed pump intensity in a five-level Λ-type system formed by the D2 transition of 85Rb. For a constant pump intensity, we find that the EIT width and height change with the variation of probe intensity. We observe a nonlinear variation of the height of the EIT peak and a linear variation of the width (FWHM) of the EIT signal with probe intensity. In the Doppler broadened multilevel system, we also observe the velocity selective dips along with the EIT signal. A numerical simulation of the probe response signal based on density matrix representation in a five-level system is carried out to reproduce the experimentally observed spectra.
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, 2009