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Title: Crystal-momentum-resolved contributions to high-order harmonic generation in solids
We analytically and numerically investigate the emission of high-order harmonic radiation from model solids by intense few-cycle midinfrared laser pulses. In single-active-electron approximation, we expand the active electron’s wave function in a basis of adiabatic Houston states and describe the solid’s electronic band structure in terms of an adjustable Kronig-Penney model potential. For high-order harmonic generation (HHG) from MgO crystals, we examine spectra from two-band and converged multiband numerical calculations. We discuss the characteristics of intra- and interband contributions to the HHG spectrum for computations including initial crystal momenta either from the  point at the center of the first Brillouin zone (BZ) only or from the entire first BZ. For sufficiently high intensities of the driving laser field, we find relevant contributions to HHG from the entire first BZ. Based on numerically calculated spectra, we scrutinize the cutoff harmonic orders as a function of the laser peak intensity and find good qualitative agreement with our analytical saddle-point-approximation predictions and published theoretical data.  more » « less
Award ID(s):
1802085
PAR ID:
10168257
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Physical review and Physical review letters index
Volume:
100
Issue:
033405
ISSN:
0094-0003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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