A new scheme to generate isolated attosecond pulses is presented that involves the use of a laser field and of a unipolar field. The laser field has a pulse of intensity I¼1.5 1014Wcm 2 and wavelength ¼820 nm. The unipolar pulse is an asymmetric pulse consisting of a sharp peak, lasting approximately half a laser period, i.e. nearly 1.4 fs, followed by a long and shallow tail. We show that on combining these two fields, it is possible to generate isolated attosecond pulses as short as 1/10 of a laser period, i.e. approximately 270 as. Moreover, it is argued that this scheme is robust either against small variations of the laser envelope, or against small changes in the delay between the laser pump and the unipolar pulse.
|Numero di pagine||7|
|Rivista||Journal of Modern Optics|
|Stato di pubblicazione||Published - 2009|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics