Figure caption: Generation of coherent X-rays from helium irradiated by a 5-femtosecond near-infrared pulse with intensity 1016 W/cm2. The purple fluorescence emission originates from ionized high- density helium gas streaming out of a thin metal tube through holes bored by the focused laser beam. The high-order harmonic (HH) radiation extends to wavelengths as short as 2 nm. The harmonics are emitted coherently in a well collimated beam collinear to the laser beam, which propagates along the axis of the purple emission. Animation from G. Tempea (TAEQ, TU-Wien).
|Scope of the special research program (text to come)|