Applied Optics
High-contrast dark resonances with linearly polarized light on the D_1 line of alkali atoms with large nuclear spin
Ken-ichi Watabe, Takeshi Ikegami, Akifumi Takamizawa, Shinya Yanagimachi, Shinichi Ohshima, Svenja A. Knappe
Abstract
High-contrast coherent population trapping signals were observed on the Cs D1 line by use of a bichromatic linear polarized light (lin‖lin field). A maximum absorption contrast of about 10% was obtained. This was nearly twice as high as that measured with the standard configuration of bichromatic circularly polarized light (σ-σ field). The results are compared with density matrix calculations of 4 and 5 level systems.