Open AccessInter-half-cycle spectral interference in high-order harmonic generation from monolayer MoS2
Author(s) -
Jiayuan Cao,
Fangshu Li,
Ya Bai,
Peng Liu,
Ruxin Li
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.416213
Subject(s) - harmonics , high harmonic generation , interference (communication) , optics , harmonic , physics , polarity (international relations) , modulation (music) , monolayer , harmonic spectrum , harmonic analysis , spectral line , materials science , laser , quantum mechanics , telecommunications , chemistry , acoustics , channel (broadcasting) , electronic engineering , voltage , nanotechnology , biochemistry , computer science , cell , engineering
The enhancement of even-order harmonics near the cut-off of high-order harmonic spectra from monolayer MoS 2 has been experimentally observed recently by several groups. Here we demonstrate that this enhancement can be interpreted as a result of spectral interference between half-cycles with opposite polarity by adopting a fully quantum mechanical calculation. We found that, due to the energy modulation induced by Berry connections, only half-cycles with the same polarity can generate high-order harmonics near the cut-off frequency, thus the lack of destructive interference leads to the enhanced intensity of the corresponding even-order harmonics. The explanation is supported by the frequency shift of the measured harmonic peaks. Our finding revealed the role of inter-half-cycle interference in high-harmonic generation (HHG) from non-centrosymmetric materials.