CESIUM SATURATION SPECTROSCOPY REVISITED - HOW TO REVERSE PEAKS AND OBSERVE NARROW RESONANCES

The complex magnetic structure of the cesium atom is responsible for t he interesting behaviour of its saturated absorption spectra, e.g., a two-fold sign reversal of a crossover resonance, under various polariz ation configurations with and without applied magnetic fields. We show that this morphology is a result of optical pumping processes includi ng coherent population trapping which, under normal laboratory conditi ons, prevent the atoms from reaching an equilibrium situation. Our int erpretation is useful for an intuitive and rapid understanding of this important tool in high-resolution spectroscopy.