Impact of donor and acceptor dopants in high-harmonic generation spectra of solids

High-order harmonic generation (HHG) from solids is one source of coherent extreme ultraviolet radiation and is considered as a promising way to obtain attosecond pulses, where the key issue is to enhance HHG yield and control its temporal characteristic. The role of the dopant on enhancement of HHG yield is investigated via solving the time-dependent Schrodinger equation. We find that the doped solids possessing an impurity band in the middle of the bandgap can achieve time-domain optimization and yield enhancement in the bursts of HHG. The reason for the enhanced HHG yield is that the impurity band can provide a ladder in the step-by-step transition process. The difference in the Bloch–Zener oscillation dynamics between pristine and doped solids is shown, which also influences the variation of HHG yield and generation of even-order harmonics. In addition, the avoided level crossing between conduction bands assists the promotion of electrons and leads to the mergence between primary and secondary plateaus under nondestructive laser intensity. Finally, the generation of shorter and efficient attosecond pulses is obtained theoretically from the doped solids.