posted on 2025-01-20, 06:37authored byXi Zhao, Jiahao Liu, Shicheng Jiang, Jigen Chen, Jun Wang, Song Zhang
The dephasing time \(T_2\) is an important parameter in quantum information, optics and condensed matter physics, particularly in the context of ultrafast carrier dynamics and quantum coherence when solids are subjected to intense laser irradiation. However, understanding the precise dephasing mechanisms and directly measuring \(T_2\) from experimental spectra remains elusive, hindering our understanding of the physics of condense state systems under extreme conditions. In this work, through the Quantum Complex Analysis model, where all physical quantities are treated as complex values, we clearly elucidate that the quantum tunneling process of carriers between different energy bands in solids makes a significant contribution to the dephasing time. The ability to accurately describe the \( T_2 \) term directly determines the laser-induced tunneling process of carriers and the interference patterns of long and short quantum orbital in High-order Harmonic Generation (HHG). Consequently, the dephasing rate is encoded in the HHG spectra, providing an opportunity to reconstruct \(T_2\) from experimental HHG spectra using machine learning techniques. Our work makes a novel contribution to the study and understanding of dephasing time in solid HHG by addressing both the direct reconstruction of \(T_2\) from experimental data and its underlying physical effects. In addition, Our reconstruction algorithm also provides a possible method for studying the quantum tunneling process of light-induced carrier transitions between different energy bands.