Abstract

We report the demonstration of near-quantum-noise-limited sensitivity with a lead-salt diode laser using FM spectroscopy and high-speed sweep integration. Using both single-tone and two-tone techniques, we demonstrated an absorption sensitivity of ~2 × 10⁻⁷ in a 2.44-Hz bandwidth from a Doppler-broadened NO line at 1856.5 cm⁻¹. The sensitivity in our experiments was limited by laser excess noise, which was about four times the expected quantum-noise level.

© 1988 Optical Society of America

Quantum noise-limited FM spectroscopy with a lead-salt diode laser

Clinton B. Carlisle, David E. Cooper, and Horst Preier
Appl. Opt. 28(13) 2567-2576 (1989)

Two-tone optical heterodyne spectroscopy with a tunable lead-salt diode laser

David E. Cooper and J. P. Watjen
Opt. Lett. 11(10) 606-608 (1986)

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)

High-frequency-modulation spectroscopy with a lead-salt diode laser

Manfred Gehrtz, Wilfried Lenth, Anthony T. Young, and Harold S. Johnston
Opt. Lett. 11(3) 132-134 (1986)

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)