- Broida 1640
Mark Sherwin - UCSB
Intense laser fields can rip electrons from an atom and slam them back into it. By using intense terahertz radiation from UC Santa Barbara’s Free-Electron Lasers, we have observed an analogous phenomenon for photo-excited electrons and holes in a semiconductor. A trillion energetic electron-hole collisions per second convert a monochromatic near-infrared laser beam at 350 THz(0.8 µm) into a polychromatic near-infrared beam containing up to 11 new frequencies spaced by 1 Terahertz. Implications for the nature of optical excitations in solids and possible applications to optical communications will be discussed.