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arXiv · 1803.00623

Phase-stabilized 100 mW frequency comb near 10 μm

Kana Iwakuni·Gil Porat·Thinh Q. Bui·Bryce J. Bjork·Stephen B. Schoun·Oliver H. Heckl·Martin E. Fermann·Jun Ye
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Abstract

Long-wavelength mid-infrared frequency combs with high power and flexible tunability are highly desired for molecular spectroscopy, including investigation of large molecules such as C60. We present a high power, phase-stabilized frequency comb near 10 μm, generated by a synchronously-pumped, singly-resonant optical parametric oscillator (OPO) based on AgGaSe2. The OPO can be continuously tuned from 8.4 to 9.5 μm, with a maximum average idler power of 100 mW at the center wavelength of 8.5 μm. Both the repetition rate (frep) and the carrier-envelop offset frequency (fceo) of the idler wave are phase-locked to microwave signals referenced to a Cs clock. We describe the detailed design and construction of the frequency comb, and discuss potential applications for precise and sensitive direct frequency comb spectroscopy.

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Kana Iwakuni, Gil Porat, Thinh Q. Bui, Bryce J. Bjork, Stephen B. Schoun, Oliver H. Heckl, Martin E. Fermann, Jun Ye. 2018-03-01. Phase-stabilized 100 mW frequency comb near 10 μm. https://doi.org/10.1007/s00340-018-6996-8

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