Extreme-ultraviolet high-harmonic generation in liquids.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30213950.
- Also identified by DOI 10.1038/s41467-018-06040-4 and PMC identifier 6137105.
- 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
High-harmonic generation (HHG) in gases has been the main enabling technology of attosecond science since its discovery. Recently, HHG from solids has been demonstrated, opening a lively area of research. In contrast, harmonic generation from liquids has so far remained restricted to low harmonics in the visible regime. Here, we report the observation and detailed characterization of extreme ultraviolet HHG from liquid water and several alcohols extending beyond 20 eV. This advance was enabled by the implementation of the recent liquid flat-microjet technology, which we show to facilitate the spatial separation of HHG from the bulk liquid and the surrounding gas phase. We observe striking differences between the HHG spectra of water and several alcohols. A comparison with a strongly-driven few-band model establishes the sensitivity of HHG to the electronic structure of liquids. Our results suggest liquid-phase high-harmonic spectroscopy as a new method for studying the electronic structure and ultrafast scattering processes in liquids.