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Title: Explicit formula for high-order sideband polarization by extreme tailoring of Feynman path integrals
High-order sideband generation (HSG), as an analog of the interband processes in high-harmonic generation (HHG) in solids, is a nonperturbative nonlinear optical phenomenon in semiconductors that are simultaneously driven by a relatively weak near-infrared (NIR) laser and a sufficiently strong terahertz (THz) field. We derive an explicit formula for sideband polarization vectors in a prototypical two-band model based on the saddle-point method. Our formula connects the sideband amplitudes with the laser-field parameters, electronic structures, and nonequilibrium dephasing rates in a highly nontrivial manner. Our results indicate the possibility of extracting information on band structures and dephasing rates from high-order sideband generation experiments with simple algebraic calculations. We also expect our approach to be useful on the quantitative understanding of the interband HHG.  more » « less
Award ID(s):
2004995
PAR ID:
10470515
Author(s) / Creator(s):
;
Publisher / Repository:
Physical Review B
Date Published:
Journal Name:
Physical Review B
Volume:
107
Issue:
17
ISSN:
2469-9950
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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