论文标题
Terahertz频率的Ingaas纳米线的非线性电荷运输
Nonlinear Charge Transport in InGaAs Nanowires at Terahertz Frequencies
论文作者
论文摘要
我们使用宽带THZ脉冲和高达0.6 mV/cm的峰值电场探测高电场的GAAS/IN0.2GA0.8AS芯/壳纳米线的电子传输性能。光激发电荷载体的等离子体共振表现出系统的红移，并抑制其光谱重量超过0.4 mV/cm。该行为归因于间隔电子散射，导致平均电子有效质量的增加以及电子迁移率在最高场上的相应降低约2倍。我们证明，有效质量的增加沿纳米线是不均匀的，主要发生在其中部，从而导致空间不均匀的载体反应。我们的结果量化了基于GAAS的纳米线中的非线性传输状态，并显示出它们在THZ频率下运行的纳米设备开发的高潜力。
We probe the electron transport properties in the shell of GaAs/In0.2Ga0.8As core/shell nanowires at high electric fields using optical pump / THz probe spectroscopy with broadband THz pulses and peak electric fields up to 0.6 MV/cm. The plasmon resonance of the photoexcited charge carriers exhibits a systematic redshift and a suppression of its spectral weight for THz driving fields exceeding 0.4 MV/cm. This behavior is attributed to the intervalley electron scattering resulting in the increase of the average electron effective mass and the corresponding decrease of the electron mobility by about 2 times at the highest fields. We demonstrate that the increase of the effective mass is non-uniform along the nanowires and takes place mainly in their middle part, leading to a spatially inhomogeneous carrier response. Our results quantify the nonlinear transport regime in GaAs-based nanowires and show their high potential for development of nano-devices operating at THz frequencies.
