Electromagnetically induced transparency in Λ-type Zeeman sublevels of cesium atoms

Employing two lasers as the coupling and probe fields which have opposite circular polarization (σ⁺ and σ^-), electromagnetically induced transparency (EIT) in Λ-type Zeeman sublevels of cesium 6²S_1/2F = 3-6²P_3/2F′ = 2 degenerate two-level system has been demonstrated via probe absorption spectra. The effect of the intensity and detuning of different coupling Laser on EIT was also investigated in experiments. Within the Doppler background, optical pumping among Zeeman sub-levels and the population of different Zeeman sub-levels can dominate the intensity of EIT effect. And the physical reasons of the rugged spectra are presented qualitatively.