title: Silicon-chip mid-infrared frequency comb generation.
abstract: Optical frequency combs are a revolutionary light source for high-precision spectroscopy because of their narrow linewidths and precise frequency spacing. Generation of such combs in the mid-infrared spectral region (2-20 μm) is important for molecular gas detection owing to the presence of a large number of absorption lines in this wavelength regime. Microresonator-based frequency comb sources can provide a compact and robust platform for comb generation that can operate with relatively low optical powers. However, material and dispersion engineering limitations have prevented the realization of an on-chip integrated mid-infrared microresonator comb source. Here we demonstrate a complementary metal-oxide-semiconductor compatible platform for on-chip comb generation using silicon microresonators, and realize a broadband frequency comb spanning from 2.1 to 3.5 μm. This platform is compact and robust and offers the potential to be versatile for use outside the laboratory environment for applications such as real-time monitoring of atmospheric gas conditions.
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Austin G
authors.initials: AG
authors.lastname: Griffith
authors.affiliation: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Ryan K W
authors.initials: RK
authors.lastname: Lau
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Jaime
authors.initials: J
authors.lastname: Cardenas
authors.affiliation: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Yoshitomo
authors.initials: Y
authors.lastname: Okawachi
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Aseema
authors.initials: A
authors.lastname: Mohanty
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Romy
authors.initials: R
authors.lastname: Fain
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Yoon Ho Daniel
authors.initials: YH
authors.lastname: Lee
authors.affiliation: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Mengjie
authors.initials: M
authors.lastname: Yu
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Phare
authors.affiliation: School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA.
authors.forename: Carl B
authors.initials: CB
authors.lastname: Poitras
authors.affiliation: 1] School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA [2] Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Gaeta
authors.affiliation: 1] School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850, USA [2] Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Michal
authors.initials: M
authors.lastname: Lipson