High-order parametric generation of coherent XUV radiation
arXiv:2005.06415 · doi:10.1364/OE.418449
Abstract
We observe a new regime of coherent XUV radiation generation in noble gases induced by femtosecond pulses at very high intensities. This XUV emission has both a reduced divergence and spectral width as compared to high-order harmonic generation (HHG). It is not emitted at a moderate intensity of the driving pulses where only high-order harmonics are generated. At high driving intensities, the additional XUV comb appears near all harmonic orders and even exceeds the HHG signal on the axis. The peaks are observed in several gases and their frequencies do not depend on the driving intensity or gas pressure. We analyze the divergence, spectral width and spectral shift of this XUV emission. We show that these specific features are well explained by high-order parametric generation (HPG) involving multiphoton absorption and combined emission of an idler THz radiation and an XUV beam with remarkably smooth spatial and spectral characteristics.
18 pages, 12 figures. To be published in a peer-reviewed scientific journal
References in corpus (8)
- Phase-Matched Generation of Coherent Soft-X-Rays
- Determination of the Carrier-Envelope Phase of Few-Cycle Laser Pulses with Terahertz-Emission Spectroscopy
- Role of Excited States In High-order Harmonic Generation
- Controlled free-induction decay in the extreme ultraviolet
- Spectrally resolved spatiotemporal features of quantum paths in high-order harmonic generation
- Multiple ionization of argon via xuv-photon absorption induced by 20-gigawatt high-harmonic pulses
- Phase-Resolved Two-Dimensional Spectroscopy of Electronic Wavepackets by Laser-Induced XUV Free Induction Decay
- High-order optical processes: towards nonperturbative nonlinear optics