부산대학교 도서관

The effect of crystal symmetry in the high harmonic generation of monolayer WS2 is investigated using the three‐dimensional time‐dependent density functional theory. The role of linearly and elliptically polarized laser, as well as the crystall orientation in the enhancement of harmonics yield, is explored. Also, the wavelength dependence of the harmonic yield and the intensity dependence of cutoff harmonic order are studied. The former shows an exponential decay with increasing the driving laser wavelength, and the latter reveals a linear dependency of cutoff harmonic to the driving laser field. Moreover, a dual pulse system as a driving laser, a fundamental 1.3 μm laser pulse synthesized by its second harmonic, is proposed which could increase the cutoff harmonic order up to 24th (22 eV). Our results pave the way for controlling and enhancing high harmonic spectra from solids. [ABSTRACT FROM AUTHOR]