Decoherence Effects of Terahertz Generation in Solids under Two-Color Femtosecond Laser Fields

• 作者: Qifang Peng Zhaoyang Peng Yue Lang Yalei Zhu Dongwen Zhang Zhihui Lü Zengxiu Zhao
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2022,（5）
• 所属期刊栏目: ATOMIC AND MOLECULAR PHYSICS
• 页码范围: 55-60
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/0256-307X/39/5/053301

摘要

We theoretically investigate terahertz emission from solid materials pumped by intense two-color femtosecond laser field in the presence of decoherence effects.Quantum-mechanical simulations are based on the length gauge semiconductor Bloch equations describing the optical excitation and decoherence with phenomenological dephasing and depopulation times.Contributions of interband and intraband mechanisms are identified in time domain,and the latter has dominated THz generation in solid-state systems.It is found that dephasing is crucial for enhancing asymmetric intraband current and deduced that solid-state materials with short dephasing time and long depopulation time would be optimal selection for strong-field terahertz generation experiments.