Photonic chip-based soliton frequency combs covering the biological imaging window.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29559634.
- Also identified by DOI 10.1038/s41467-018-03471-x and PMC identifier 5861103.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Dissipative Kerr solitons (DKS) in optical microresonators provide a highly miniaturised, chip-integrated frequency comb source with unprecedentedly high repetition rates and spectral bandwidth. To date, such frequency comb sources have been successfully applied in the optical telecommunication band for dual-comb spectroscopy, coherent telecommunications, counting of optical frequencies and distance measurements. Yet, the range of applications could be significantly extended by operating in the near-infrared spectral domain, which is a prerequisite for biomedical and Raman imaging applications, and hosts commonly used optical atomic transitions. Here we show the operation of photonic-chip-based soliton Kerr combs driven with 1 micron laser light. By engineering the dispersion properties of a Si<sub>3</sub>N<sub>4</sub> microring resonator, octave-spanning soliton Kerr combs extending to 776 nm are attained, thereby covering the optical biological imaging window. Moreover, we show that soliton states can be generated in normal group-velocity dispersion regions when exploiting mode hybridisation with other mode families.