Electromagnetically induced transparency in cesium

A ladder-type electromagnetically induced transparency (EIT) is investigated in cesium gas. We use two homemade external-cavity diode lasers (ECDL) to produce a weak probe beam at 852.3 nm (6S_1/2 → 6P_3/2) and a strong coupling beam at 520.3 nm (6P_3/2 → 18D_5/2). Results are compared with the theoretical predictions. This experiment has the potential to develop an advanced undergraduate laboratory in quantum optics using similar equipment used in traditional absorption spectroscopy.