Abstract
The phase-matching condition of high-order harmonic generation driven by intense few-cycle pulses could be controlled by adding second-harmonic pulses to change the ionization fraction of the gaseous medium. The harmonic generation efficiency could be improved by moving the phase-matching point with an all-optical control of the ionization fraction or a proper change of the confocal parameter. A specific order of harmonics could be easily controlled to reach phase matching at a fixed higher gas pressure by adding second-harmonic pulses with a suitable intensity. Such an all-optical phase-matching control was demonstrated to be dependent upon the temporal delay between the fundamental-wave and second harmonic pulses.
| Original language | English |
|---|---|
| Article number | 063823 |
| Journal | Physical Review A - Atomic, Molecular, and Optical Physics |
| Volume | 76 |
| Issue number | 6 |
| DOIs | |
| State | Published - 28 Dec 2007 |
| Externally published | Yes |