Researchers use plasmonic nanofocusing of near-infrared pulses in metallic tapered gap waveguides to generate ultrashort extreme-ultraviolet pulses. They calculate that the electromagnetic field intensity is around 350 times higher than that of a reference untapered waveguide, allowing harmonics up to the 43rd to be realized at a modest incident intensity of ∼1011 W cm−2.
- In-Yong Park
- Seungchul Kim
- Seung-Woo Kim