High-harmonic generation by field enhanced femtosecond pulses in metal-sapphire nanostructure.

ABSTRACT: Plasmonic high-harmonic generation (HHG) drew attention as a means of producing coherent extreme ultraviolet (EUV) radiation by taking advantage of field enhancement occurring in metallic nanostructures. Here a metal-sapphire nanostructure is devised to provide a solid tip as the HHG emitter, replacing commonly used gaseous atoms. The fabricated solid tip is made of monocrystalline sapphire surrounded by a gold thin-film layer, and intended to produce EUV harmonics by the inter- and intra-band oscillations of electrons driven by the incident laser. The metal-sapphire nanostructure enhances the incident laser field by means of surface plasmon polaritons, triggering HHG directly from moderate femtosecond pulses of ∼0.1 TW cm^-2 intensities. The measured EUV spectra exhibit odd-orde

SUBMITTER: Han S 

PROVIDER: S-EPMC5062548 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature