article published Xunqin Huo author Xiwang Liu author Shidong Yang author Xiaohong Song author Torsten Meier author 3440000-0001-8864-2072 Weifeng Yang author 15 department 170 department 293 department 230 department 623 department <jats:p> High-harmonic generation in solids enables probing of strong-field electron dynamics in condensed matter and the development of compact ultrafast light sources. Whereas most studies have focused on above-bandgap high-order harmonics, which are usually interpreted through short electron-hole trajectories that recombine within one optical cycle, the microscopic origin of low-order emission near the bandgap remains poorly understood. Here, we investigate near-bandgap harmonic generation in ZnO by combining semiconductor Bloch equations with a complex-time quantum-trajectory analysis. Our results indicate that these harmonics are not a continuation of the short trajectory. Rather, they originate from multiple-scattering trajectories, in which the electron-hole pair undergoes repeated Bragg scattering at the Brillouin-zone boundary and electron-hole reencounter near the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mi mathvariant="normal">Γ</a:mi> </a:math> point before the actual recombination occurs. We identify that the imaginary part of the electron-hole displacement provides a practical diagnostic of the residual tunneling memory. Real-space electron-hole overlap alone does not imply coherent recombination unless the full complex displacement vanishes. These results clarify the microscopic picture of near-bandgap harmonic emission in ZnO and offer a framework for interpreting phase-resolved strong-field dynamics in solids. </jats:p> American Physical Society (APS)2026 eng 2643-156410.1103/l939-jglf 83 @article{Huo_Liu_Yang_Song_Meier_Yang_2026, title={Near-bandgap harmonic generation in solids from multiple scattering revealed by complex quantum trajectories}, volume={8}, DOI={<a href="https://doi.org/10.1103/l939-jglf">10.1103/l939-jglf</a>}, number={3033303}, journal={Physical Review Research}, publisher={American Physical Society (APS)}, author={Huo, Xunqin and Liu, Xiwang and Yang, Shidong and Song, Xiaohong and Meier, Torsten and Yang, Weifeng}, year={2026} } Huo X, Liu X, Yang S, Song X, Meier T, Yang W. Near-bandgap harmonic generation in solids from multiple scattering revealed by complex quantum trajectories. <i>Physical Review Research</i>. 2026;8(3). doi:<a href="https://doi.org/10.1103/l939-jglf">10.1103/l939-jglf</a> Huo, Xunqin, et al. “Near-Bandgap Harmonic Generation in Solids from Multiple Scattering Revealed by Complex Quantum Trajectories.” <i>Physical Review Research</i>, vol. 8, no. 3, 033303, American Physical Society (APS), 2026, doi:<a href="https://doi.org/10.1103/l939-jglf">10.1103/l939-jglf</a>. Huo, Xunqin, Xiwang Liu, Shidong Yang, Xiaohong Song, Torsten Meier, and Weifeng Yang. “Near-Bandgap Harmonic Generation in Solids from Multiple Scattering Revealed by Complex Quantum Trajectories.” <i>Physical Review Research</i> 8, no. 3 (2026). <a href="https://doi.org/10.1103/l939-jglf">https://doi.org/10.1103/l939-jglf</a>. X. Huo, X. Liu, S. Yang, X. Song, T. Meier, W. Yang, Physical Review Research 8 (2026). X. Huo, X. Liu, S. Yang, X. Song, T. Meier, and W. Yang, “Near-bandgap harmonic generation in solids from multiple scattering revealed by complex quantum trajectories,” <i>Physical Review Research</i>, vol. 8, no. 3, Art. no. 033303, 2026, doi: <a href="https://doi.org/10.1103/l939-jglf">10.1103/l939-jglf</a>. Huo, X., Liu, X., Yang, S., Song, X., Meier, T., &#38; Yang, W. (2026). Near-bandgap harmonic generation in solids from multiple scattering revealed by complex quantum trajectories. <i>Physical Review Research</i>, <i>8</i>(3), Article 033303. <a href="https://doi.org/10.1103/l939-jglf">https://doi.org/10.1103/l939-jglf</a> 671462026-09-15T06:50:14Z2026-09-15T06:51:05Z