Stark spectroscopy with the CO laser: Lamb dip spectra of H217O and H218O in the ν2 fundamental band

Abstract

Saturated absorption spectra of four different transitions in the ν2 fundamental bands of H217O and H218O have been observed using the technique of intracavity CO laser Stark spectroscopy. The analysis of these spectra yields a direct measurement of the dipole moment change between the ground vibrational state and the ν2 = 1 state of H217O, as well as the zero-field frequencies for the observed transitions. A collision-induced centre dip ('crossover resonance') which occurs in one spectrum is formed in a four-level system that is probably the most nearly isolated of any yet observed.