Degenerate four-wave mixing and polarization spectroscopy in NO 2

Abstract

Degenerate Four Wave Mixing (DFWM) and polarization spectroscopy (PS) have been used to detect traces of nitric dioxide in a static cell at room temperature and in a small flame from a laboratory Bunsen burner. The high resolution spectrum of the Douglas-Huber band has been recorded with both techniques. The role played by population and thermal gratings in the DFWM case has been investigated under various experimental conditions. PS measurements performed with 'orientation' and 'alignment' configurations allowed to resolve NO<SUB>2</SUB> composite spectral features.