Near-infrared to ultra-violet frequency conversion in chalcogenide metasurfaces.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34611169.
- Also identified by DOI 10.1038/s41467-021-26094-1 and PMC identifier 8492647.
- 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
Chalcogenide photonics offers unique solutions for a broad range of applications from mid-infrared sensing to integrated, ultrafast, ultrahigh-bandwidth signal processing. However, to date its usage has been limited to the infrared part of the electromagnetic spectrum, thus avoiding ultraviolet and visible ranges due to absorption of chalcogenide glasses. Here, we experimentally demonstrate and report near-infrared to ultraviolet frequency conversion in an As<sub>2</sub>S<sub>3</sub>-based metasurface, enabled by a phase locking mechanism between the pump and the inhomogeneous portion of the third harmonic signal. Due to the phase locking, the inhomogeneous component co-propagates with the pump pulse and encounters the same effective dispersion as the infrared pump, and thus experiences little or no absorption, consequently opening previously unexploited spectral range for chalcogenide glass science and applications, despite the presence of strong material absorption in this range.