title: Asynchronous midinfrared ultrafast optical parametric oscillator for dual-comb spectroscopy.
abstract: Two asynchronous, broadband 3.3 µm pulse trains with a stabilized repetition-rate difference of up to 5 kHz were generated using an ultrafast optical parametric oscillator. The two oscillation channels, each producing ~100 mW average power, ran essentially independently, and weak non-phase-matched sum-frequency mixing between them provided a timing signal that indicated when the asynchronous pulses coincided. The system has immediate applications in incoherent asynchronous optical sampling and, with additional carrier-envelope-offset stabilization, could be applied to coherent dual-frequency-comb spectroscopy.
authors.affiliation: Scottish Universities Physics Alliance (SUPA), Department of Physics, School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton, Edinburgh, UK. z.zhang@hw.ac.uk
authors.forename: Zhaowei
authors.initials: Z
authors.lastname: Zhang
authors.forename: Chenglin
authors.initials: C
authors.lastname: Gu
authors.forename: Jinghua
authors.initials: J
authors.lastname: Sun
authors.forename: Chingyue
authors.initials: C
authors.lastname: Wang
authors.forename: Tom
authors.initials: T
authors.lastname: Gardiner
authors.forename: Derryck T
authors.initials: DT
authors.lastname: Reid