title: Demonstration of a near-IR line-referenced electro-optical laser frequency comb for precision radial velocity measurements in astronomy.
abstract: An important technique for discovering and characterizing planets beyond our solar system relies upon measurement of weak Doppler shifts in the spectra of host stars induced by the influence of orbiting planets. A recent advance has been the introduction of optical frequency combs as frequency references. Frequency combs produce a series of equally spaced reference frequencies and they offer extreme accuracy and spectral grasp that can potentially revolutionize exoplanet detection. Here we demonstrate a laser frequency comb using an alternate comb generation method based on electro-optical modulation, with the comb centre wavelength stabilized to a molecular or atomic reference. In contrast to mode-locked combs, the line spacing is readily resolvable using typical astronomical grating spectrographs. Built using commercial off-the-shelf components, the instrument is relatively simple and reliable. Proof of concept experiments operated at near-infrared wavelengths were carried out at the NASA Infrared Telescope Facility and the Keck-II telescope.
authors.affiliation: Department of Applied Physics and Materials Science, Pasadena, California 91125, USA.
authors.forename: X
authors.initials: X
authors.lastname: Yi
authors.affiliation: Department of Applied Physics and Materials Science, Pasadena, California 91125, USA.
authors.forename: K
authors.initials: K
authors.lastname: Vahala
authors.affiliation: Department of Applied Physics and Materials Science, Pasadena, California 91125, USA.
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.affiliation: National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA.|Department of Physics, University of Colorado, 2000 Colorado Avenue, Boulder, Colorado 80309, USA.
authors.forename: S
authors.initials: S
authors.lastname: Diddams
authors.affiliation: National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA.|Department of Physics, University of Colorado, 2000 Colorado Avenue, Boulder, Colorado 80309, USA.
authors.forename: G
authors.initials: G
authors.lastname: Ycas
authors.affiliation: Department of Physics, Missouri State University, 901 S National Avenue, Springfield, Missouri 65897, USA.
authors.forename: P
authors.initials: P
authors.lastname: Plavchan
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
authors.forename: S
authors.initials: S
authors.lastname: Leifer
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
authors.forename: J
authors.initials: J
authors.lastname: Sandhu
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
authors.forename: G
authors.initials: G
authors.lastname: Vasisht
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
authors.forename: P
authors.initials: P
authors.lastname: Chen
authors.affiliation: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: P
authors.initials: P
authors.lastname: Gao
authors.affiliation: Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, Washington, District of Columbia 20015, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gagne
authors.affiliation: NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: E
authors.initials: E
authors.lastname: Furlan
authors.affiliation: Department of Astronomy, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: M
authors.initials: M
authors.lastname: Bottom
authors.affiliation: Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA.
authors.forename: E C
authors.initials: EC
authors.lastname: Martin
authors.affiliation: Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Fitzgerald
authors.affiliation: W.M. Keck Observatory, Kamuela, Hawaii 96743, USA.
authors.forename: G
authors.initials: G
authors.lastname: Doppmann
authors.affiliation: NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: C
authors.initials: C
authors.lastname: Beichman
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