Stark modulation spectrometer using a wideband Zeeman-tuned He-Xe laser

A 200 GHz-tunable 3.51 μm He−Xe laser is employed in Stark-modulation spectroscopy, and good performance of the spectrometer is demonstrated by an exemplary measurement on the HDO spectrum. Various spectral features and the anomalous line shapes due to the Stark effect are interpreted and used as an important clue to identification of the absorption lines.