Crystal orientation-dependent polarization state of high-order harmonics
Abstract
We analyze the crystal orientation-dependent polarization state of extreme ultraviolet (XUV) high-order harmonics from bulk magnesium oxide crystals subjected to intense linearly polarized laser fields. We find that only along high-symmetry directions in crystals high-order harmonics follow the polarization direction of the laser field. In general, the polarization direction of high-order harmonics deviates from that of the laser field, and the deviation amplitude depends on the crystal orientation, harmonic order and the strength of the laser field. We use a real-space electron trajectory model to understand the crystal orientation-dependent polarization state of XUV harmonics. The polarization analysis allows us to track the motion of strong-field-driven electron in conduction bands in two dimensions. These results have implications in all-optical probing of atomic-scale structure in real-space, electronic band-structure in momentum space, and in the possibility of generating attosecond pulses with time-dependent polarization in a compact setup.
- Publication:
-
Optics Letters
- Pub Date:
- February 2019
- DOI:
- 10.1364/OL.44.000530
- arXiv:
- arXiv:1810.11567
- Bibcode:
- 2019OptL...44..530Y
- Keywords:
-
- Physics - Optics
- E-Print:
- 5 pages, 5 figures