Time-resolved UV-IR pump-stimulated emission pump spectroscopy to probe collisional relaxation of the 8p2P3/2 state of Cs I

We describe and use a time-resolved pump-stimulated emission pump spectroscopic technique to measure collisional relaxation in a high-lying energy level of atomic cesium. Aligned 8p2P3/2 cesium atoms were produced by a pump laser. A second laser, the stimulated emission pump, promoted the population exclusively to the 5d2D5/2 level. The intensity of the 5dD5/22→6sS1/22 cascade fluorescence at 852.12 nm was monitored. The linear polarization dependence of the 6sS1/22→8pP3/22→5dS5/22 transition was measured in the presence of argon gas at various pressures. From the measurement, we obtained the disalignment cross sectional value for the 8p2P3/2 level due to collisions with ground-level argon atoms.