Saturated resonance spectroscopy of SiF4

Abstract

The small-signal absorption coefficient of silicon tetrafluoride (SiF4) at the 9.6-μm CO2 laser wavelength has been measured by means of saturated spectroscopy. The Lamb dip spectrum of the SiF4 transitions in coincidence with five CO2 9.6-μm P-branch transitions has been observed. Measurements of the pressure dependence of the Lamb dip width were made, resulting in a determination of the SiF4–SiF4 cross section for phase interruption collisions. The saturation intensity was experimentally found to be quadratic with pressure, in a limited pressure range, and an upper bound for the Einstein A coefficient was determined.