https://doi.org/10.1051/epjconf/202125511002
Efficient carrier-envelope phase tunable mid-infrared frequency combs based on CW-seeded optical parametric generation
1 Department of Chemistry, University of Helsinki, FI-00560, Helsinki, Finland
2 HC Photonics Corp. Hsinchu Science Park, Hsinchu 30078, Taiwan
3 Metrology Research Institute, Aalto University, Espoo, FI-00076, Finland
4 Photonics Laboratory, Physics Unit, Tampere University, Tampere, FI-33101, Finland
* Corresponding author: mikhail.roiz@helsinki.fi
Published online: 18 November 2021
We present an efficient method for generating frequency combs in the mid-infrared (MIR) spectral range in bulk lithium niobate crystals as well as in waveguides. Our approach is simple and robust, since it is based on single-pass configuration of femtosecond Optical Parametric Generation (OPG) seeded by a telecom continuous-wave laser. Precise and fast tuning of the seed laser allows to rapidly change the offset frequency of the generated MIR comb independent of its repetition rate. The MIR comb offset frequency is inherently known, so its direct detection is not required. An additional degree of freedom that further complements the versatility of our light source is a unique way of repetition rate or mode spacing adjustments. This is achieved by our new concept of coherent multi-seeding that depending on the configuration allows for pulse train modulation and mode spacing, or repetition rate division by an integer number.
© The Authors, published by EDP Sciences, 2021
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
