An octave-spanning mid-infrared frequency comb generated in a silicon nanophotonic wire waveguide
Abstract
Laser frequency combs, sources with a spectrum consisting of hundred thousands evenly spaced narrow lines, have an exhilarating potential for new approaches to molecular spectroscopy and sensing in the mid-infrared region. The generation of such broadband coherent sources is presently under active exploration. Technical challenges have slowed down such developments. Identifying a versatile highly nonlinear medium for significantly broadening a mid-infrared comb spectrum remains challenging. Here we take a different approach to spectral broadening of mid-infrared frequency combs and investigate CMOS-compatible highly nonlinear dispersion-engineered silicon nanophotonic waveguides on a silicon-on-insulator chip. We record octave-spanning (1,500-3,300 nm) spectra with a coupled input pulse energy as low as 16 pJ. We demonstrate phase-coherent comb spectra broadened on a room-temperature-operating CMOS-compatible chip.
- Publication:
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Nature Communications
- Pub Date:
- February 2015
- DOI:
- 10.1038/ncomms7310
- arXiv:
- arXiv:1405.4205
- Bibcode:
- 2015NatCo...6.6310K
- Keywords:
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- Physics - Optics
- E-Print:
- doi:10.1038/ncomms7310