DETECTION OF POLYATOMIC-MOLECULES USING INFRARED DEGENERATE 4-WAVE-MIXING

Degenerate four-wave mixing detection of methane and acetylene is demonstrated using rotational-vibrational transitions for resonance enhancement. High resolution spectra (<0.007 cm-1) of methane and acetylene, near 3000 and 3300 cm-1 respectively, have been acquired using a single-longitudinal-mode optical parametric oscillator. These experiments suggest that infrared degenerate four-wave mixing provides a new diagnostic capability for the sensitive detection of polyatomic molecules with high temporal and spatial resolution.