Enhancing the efficiency of high-order harmonics with two-color non-collinear wave mixing in silica

• Published in: Nature communications Vol. 15; no. 1; pp. 8335 - 7
• Main Authors: Roscam Abbing, Sylvianne D. C., Kuzkova, Nataliia, van der Linden, Roy, Campi, Filippo, de Keijzer, Brian, Morice, Corentin, Zhang, Zhuang-Yan, van der Geest, Maarten L. S., Kraus, Peter M.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 27.09.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 639/624/400/3923; 639/766/36/2796; Broadband; Color; Dynamic structural analysis; Efficiency; Emission spectra; Emissions; Fused silica; Harmonic generations; Higher harmonics; Humanities and Social Sciences; Irradiation; Laser radiation; Luminous intensity; multidisciplinary; Science; Science (multidisciplinary); Silica; Solids; Ultraviolet spectra; Wavelength
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-52774-9

The emission of high-order harmonics from solids under intense laser-pulse irradiation is revolutionizing our understanding of strong-field solid-light interactions, while simultaneously opening avenues towards novel, all-solid, coherent, short-wavelength table-top sources with tailored emission profiles and nanoscale light-field control. To date, broadband spectra in solids have been generated well into the extreme-ultraviolet (XUV), but the comparatively low conversion efficiency in the XUV range achieved under optimal conditions still lags behind gas-based high-harmonic generation (HHG) sources. Here, we demonstrate that two-color high-order harmonic wave mixing in a fused silica solid is more efficient than solid HHG driven by a single color. This finding has significant implications for compact XUV sources where gas-based HHG is not feasible, as solid XUV wave mixing surpasses solid-HHG in performance. Moreover, our results enable utilizing solid high-order harmonic wave mixing as a probe of structure or material dynamics of the generating solid, which will enable reducing measurement times compared to the less efficient regular solid HHG. The emission intensity scaling that follows perturbative optical wave mixing, combined with the angular separation of the emitted frequencies, makes our approach a decisive step for all-solid coherent XUV sources and for studying light-engineered materials. High-order harmonic generation in solids could develop into a compact, coherent, short-wavelength source. This study shows that two-colour noncollinear wave mixing in silica significantly enhances HHG efficiency over single-color methods, offering a novel pathway for advancing all-solid XUV sources.