title: Adaptive real-time dual-comb spectroscopy.
abstract: The spectrum of a laser frequency comb consists of several hundred thousand equally spaced lines over a broad spectral bandwidth. Such frequency combs have revolutionized optical frequency metrology and they now hold much promise for significant advances in a growing number of applications including molecular spectroscopy. Despite an intriguing potential for the measurement of molecular spectra spanning tens of nanometres within tens of microseconds at Doppler-limited resolution, the development of dual-comb spectroscopy is hindered by the demanding stability requirements of the laser combs. Here we overcome this difficulty and experimentally demonstrate a concept of real-time dual-comb spectroscopy, which compensates for laser instabilities by electronic signal processing. It only uses free-running mode-locked lasers without any phase-lock electronics. We record spectra spanning the full bandwidth of near-infrared fibre lasers with Doppler-limited line profiles highly suitable for measurements of concentrations or line intensities. Our new technique of adaptive dual-comb spectroscopy offers a powerful transdisciplinary instrument for analytical sciences.
authors.affiliation: 1] Max Planck Institut für Quantenoptik, Laser Spectroscopy Division, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany [2].
authors.forename: Takuro
authors.initials: T
authors.lastname: Ideguchi
authors.affiliation: 1] Institut des Sciences Moléculaires d'Orsay, CNRS, Bâtiment 350, Université Paris-Sud, Orsay 91405, France [2].
authors.forename: Antonin
authors.initials: A
authors.lastname: Poisson
authors.affiliation: Institut des Sciences Moléculaires d'Orsay, CNRS, Bâtiment 350, Université Paris-Sud, Orsay 91405, France.
authors.forename: Guy
authors.initials: G
authors.lastname: Guelachvili
authors.affiliation: 1] Max Planck Institut für Quantenoptik, Laser Spectroscopy Division, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany [2] Institut des Sciences Moléculaires d'Orsay, CNRS, Bâtiment 350, Université Paris-Sud, Orsay 91405, France [3] Ludwig-Maximilians-Universität München, Fakultät für Physik, Schellingstrasse 4/III, 80799 München, Germany.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Picqué
authors.affiliation: 1] Max Planck Institut für Quantenoptik, Laser Spectroscopy Division, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany [2] Ludwig-Maximilians-Universität München, Fakultät für Physik, Schellingstrasse 4/III, 80799 München, Germany.
authors.forename: Theodor W
authors.initials: TW
authors.lastname: Hänsch
mesh_terms: D000114:Acetylene / Q000032:analysis / Q000737:chemistry; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D007834:Lasers; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000295:instrumentation* / Q000379:methods*; D013997:Time Factors
chemical_list: D000114:Acetylene