Infrared Spectroscopy of CO Using a Tunable PbSSe Diode Laser

Abstract
The P(9) fundamental infrared absorption line of carbon monoxide at 2107.4 cm−1 has been studied with high resolution using a cw current tunable PbS0.82Se0.18 diode laser. Both the Doppler linewidth of 150 MHz and the absorption coefficient at line center of 2.1 cm−1/Torr at room temperature have been measured directly for the first time with an estimated resolution of 1% of the linewidth.