Single sub-50-attosecond pulse generation from chirp-compensated harmonic radiation using material dispersion
Abstract
A method for obtaining a single sub-50-attosecond pulse using harmonic radiation is proposed. For the generation of broad harmonic radiation during a single half-optical cycle, atoms are driven by a femtosecond laser pulse with intensity above the saturation intensity for optical field ionization and hence experience a large nonadiabatic increase of the laser electric field between optical cycles. Although the chirped structure of the harmonic radiation imposes a limit on the minimum achievable pulse duration, we demonstrate that its positive chirp can be compensated by the negative group delay dispersion of an appropriately selected x-ray filter material, used also for the spectral selection, resulting in a single attosecond pulse with a duration less than 50 as .
- Publication:
-
Physical Review A
- Pub Date:
- May 2004
- DOI:
- Bibcode:
- 2004PhRvA..69e1805K
- Keywords:
-
- 42.65.Re;
- 42.50.Hz;
- 42.65.Ky;
- Ultrafast processes;
- optical pulse generation and pulse compression;
- Strong-field excitation of optical transitions in quantum systems;
- multiphoton processes;
- dynamic Stark shift;
- Frequency conversion;
- harmonic generation including higher-order harmonic generation