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Precision spectroscopy with frequency combs at 3.4 υm



Esther Baumann, Fabrizio R. Giorgetta, William C. Swann, Alexander M. Zolot, Ian R. Coddington, Nathan R. Newbury


We discuss precision spectroscopy with a comb-based spectrometer at 3.4 υm. Our goal is to explore comb-based spectroscopy as an alternative method for fast, highly resolved, accurate measurements of gas line shapes. The spectrometer uses dual 1.5 υm frequency combs down converted to 3.4 υm via difference frequency generation (DFG) with a stabilized 1 υm fiber laser. One 3.4 υm comb is transmitted through methane and heterodyned against the second, offset comb to measure the gas absorption and dispersion. Doppler-broadened methane spectral lines are measured to below 1 MHz uncertainty. We also discuss the higher sensitivity alternative of a comb-assisted swept-laser DFG spectrometer.
Proceedings Title
SPIE Optical Engineering + Applications 2011
Conference Dates
August 21-26, 2011
Conference Location
San Diego, CA


frequency combs, mid-IR, molecular spectroscopy


Baumann, E. , Giorgetta, F. , Swann, W. , Zolot, A. , Coddington, I. and Newbury, N. (2011), Precision spectroscopy with frequency combs at 3.4 υm, SPIE Optical Engineering + Applications 2011, San Diego, CA, [online], (Accessed April 19, 2024)
Created August 2, 2011, Updated February 19, 2017