Broadband Terahertz Wave Generation from Monolayer Graphene Driven by Few-Cycle Laser Pulse

• 作者: Zhong Guan Guo-Li Wang Lei Zhang Zhi-Hong Jiao Song-Feng Zhao Xiao-Xin Zhou
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: FUNDAMENTAL AREAS OF PHENOMENOLOGY(INCLUDING APPLICATIONS)
• 页码范围: 31-35
• 页数: 5页
• 语种: 英文
• DOI: 10.1088/0256-307X/38/5/054201

摘要

We theoretically investigate the characteristics of terahertz (THz) radiation from monolayer graphene exposed to normal incident few-cycle laser pulses,by numerically solving the extended semiconductor Bloch equations.Our simulations show that the THz spectra in low frequency regions are highly dependent on the carrier envelope phase (CEP) of driving laser pulses.Using an optimal CEP of few-cycle laser pulses,we can obtain broadband strong THz waves,due to the symmetry breaking of the laser-graphene system.Our results also show that the strength of the THz spectra depend on both the intensity and central wavelength of the laser pulses.The intensity dependence of the THz wave can be described by the excitation rate of graphene,while wavelength dependence can be traced back to the band velocity and the population of graphene.We find that a near single-cycle THz pulse can be obtained from graphene driven by a mid-infrared laser pulse.