Periodic decomposition picture for high-order harmonic generation in lattices with disordered dipoles

Abstract

Abstract High-order harmonic generation (HHG) in disordered condensed matter is receiving increasing attention. Meanwhile, the mechanisms of numerous ultrafast phenomena remain unknown. On the one hand, the random variables increase the difficulty of modeling and calculations. On the other hand, the complexity introduced by the disorder severely restricts the analysis of electron dynamics and underlying mechanisms. Here we establish an analytical model on the lattice representation (or the Wannier basis) in the valance and conduction bands. The original and explicit form to describe interband transitions is obtained in periodic crystals. By introducing the disorder-to-periodicity decomposition (DPD) picture, this method can be extended to certain random and disordered lattices. The DPD approximation supported by the numerical result suggests a disorder-uncorrelation perspective for the ultrafast electron dynamics driven by the laser field.