Investigating ladder-type electromagnetically induced transparency in cesium

A ladder-type electromagnetically induced transparency (EIT) is investigated in room temperature cesium gas using two external-cavity diode lasers (ECDL). A weak probe laser at 852.3 nm was scanned across the 6S_1/2 → 6P_3/2 transition while a strong coupling beam at 520.3 nm was kept at resonance with the 6P_3/2 → 18D_5/2 transition to observe EIT features in Doppler broadened absorption spectra. Results are compared with the theoretical predictions.