Regular Article

Five- and seven-level inhomogeneously broadened Ξ systems with mismatched wavelengths and polarization effects

Department of Physics, Indian Institute of Technology, Roorkee 247 667, India

^a e-mail: wasanfph@iitr.ac.in

Received: 21 November 2017
Received in final form: 7 April 2018
Published online: 5 July 2018

Abstract

We present a comparative theoretical study of the optical properties in five- (5S_1∕2 → 5P_3∕2 → 7S_1∕2) and seven-level (5S_1∕2 → 5P_3∕2 → 5D_5∕2) Ξ systems for ⁸⁷Rb atoms using density matrix formalism. We take into account the effect of wavelength mismatching, close proximity of hyperfine levels and various polarization combinations (σ⁺σ⁺, σ⁺σ⁻, πσ⁺ and ππ) of the optical fields. These factors modify the Electromagnetically induced transparency (EIT) phenomenon resulting in broadened asymmetric profile. The optical properties vary according to the level structure in both the systems. Furthermore, any change in absorption causes a concomitant modification in the dispersion and the group index.