High-order harmonic generation in a liquid-crystal-like model

The ultrafast dynamics of disordered systems have recently garnered considerable interest among researchers. However, due to the inherent complexity of such systems, many critical issues require further elucidation through extensive experimental and simulation data. We conduct calculations on high-order harmonic generation in an anisotropic two-dimensional disordered system that is similar to liquid crystals. Our results demonstrate the characteristics of harmonic spectra with different laser polarization angles and reveal a phenomenon of time delay in harmonic polarization perpendicular to the driving field. We show that this time delay arises from the intermolecular scattering of tunneling electrons before they recombine with holes. Thanks to the discovery of this phenomenon, it is hoped that polarization can be utilized to differentiate the quantum trajectories of highorder harmonics within a subcycle. Our discovery offers a different approach for investigating and manipulating ultrafast electron dynamics in condensed matter, while shedding light on the coherent control of ultrashort light sources.