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Frequency characterization of a swept and fixed-wavelength external-cavity quantum cascade laser by use of a frequency comb
Published
Author(s)
Kevin O. Knabe, Paul A. Williams, Fabrizio R. Giorgetta, Chris Armacost, Michael Radunsky, Nathan R. Newbury
Abstract
The instantaneous optical frequency of an external-cavity quantum cascade laser (QCL) is characterized by comparison to a near-infrared frequency comb. Fluctuations in the instantaneous optical frequency are analyzed to determine the frequency noise power spectral density for the external-cavity QCL both during fixed wavelength operation and swept wavelength operation. This same combination of external-cavity QCL and comb can be applied to rapid, precise broadband spectroscopy.
Knabe, K.
, Williams, P.
, Giorgetta, F.
, Armacost, C.
, Radunsky, M.
and Newbury, N.
(2012),
Frequency characterization of a swept and fixed-wavelength external-cavity quantum cascade laser by use of a frequency comb, Optics Express, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=911127
(Accessed October 23, 2025)