Degenerate Four-Wave Mixing in a Methane/Air Flame Using a Regeneratively Mode-Locked Ti:Sapphire Laser

The potential of resonant Degenerate Four-Wave Mixing (DFWM) for measurements of major and minor species concentrations and temperature in reacting flows has been established by several groups1. Spatial resolution has been demonstrated, as has two-dimensional planar imaging. Perhaps most significantly, large signals have been observed at moderately high pressures (1100 Torr)2, establishing the potential for measurements inside practical combustion systems. As a result, a good deal of research is currently devoted to understanding the fundamental physical aspects of the technique.