Abstract

This paper reports the demonstration of quantum-noise-limited sensitivity in frequency modulation spectroscopy (FMS) with a lead-salt diode laser operating in the 4.8-μm region. Experimentally determined sensitivities of 10⁻⁷ in a 1-Hz bandwidth have been demonstrated for detection of CO and CO₂ in a single-pass absorption cell. The high sensitivity obtained with our FMS apparatus can be attributed to the use of improved lead-salt diode lasers, a new optical fringe reduction method, and careful attention to optical processing of the diode laser beam.

© 1989 Optical Society of America

Wideband noise characteristics of a lead-salt diode laser: possibility of quantum noise limited TDLAS performance

Peter Werle, Franz Slemr, Manfred Gehrtz, and Christof Bräuchle
Appl. Opt. 28(9) 1638-1642 (1989)

Frequency modulation and wavelength modulation spectroscopies: comparison of experimental methods using a lead-salt diode laser

David S. Bomse, Alan C. Stanton, and Joel A. Silver
Appl. Opt. 31(6) 718-731 (1992)

Frequency modulation spectroscopy with lead–salt diode lasers: a comparison of single-tone and two-tone techniques

David E. Cooper and Russell E. Warren
Appl. Opt. 26(17) 3726-3732 (1987)

High-sensitivity FM spectroscopy with a lead-salt diode laser

David E. Cooper and Clinton B. Carlisle
Opt. Lett. 13(9) 719-721 (1988)

Two-tone optical heterodyne spectroscopy using buried double heterostructure lead–salt diode lasers

Joel A. Silver and Alan C. Stanton
Appl. Opt. 27(21) 4438-4444 (1988)