Strong-field terahertz (THz) light-matter interaction provides various nonlinear control approaches in condensed matter physics, energy and material sciences, electron acceleration, and manipulation. Recently developed spintronic THz emission with minimum complexities has been demonstrated to have the capability for generating high field strengths. Up to now, nonlinear applications based on the spintronic THz transients have yet been realized. Here, we report THz emission from two-color femtosecond laser plasma filaments modulated by a 60-kV/cm THz pulse from W/CoFeB/Pt heterostructures. Enhanced THz radiation based on electron acceleration in plasma is recorded when the direction of the spintronic THz modulating field is in line with that of the electron movement. This behavior is quantitatively reproduced by a local current model of the plasma THz source. Our experimental and theoretical results may inspire further nonlinear THz investigation and accelerate ultrafast THz engineering in matter.

中文翻译：

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通过高场自旋太赫兹脉冲在飞秒激光等离子体灯丝中产生调制太赫兹

强场太赫兹 (THz) 光-物质相互作用为凝聚态物理、能源和材料科学、电子加速和操纵提供了各种非线性控制方法。最近开发的具有最小复杂性的自旋电子太赫兹发射已被证明具有产生高场强的能力。到目前为止，尚未实现基于自旋电子太赫兹瞬变的非线性应用。在这里，我们报告了由来自 W/CoFeB/Pt 异质结构的 60-kV/cm THz 脉冲调制的双色飞秒激光等离子体灯丝的 THz 发射。当自旋电子太赫兹调制场的方向与电子运动的方向一致时，记录基于等离子体中电子加速的增强太赫兹辐射。这种行为由等离子体太赫兹源的局部电流模型定量再现。我们的实验和理论结果可能会激发进一步的非线性太赫兹研究并加速物质中的超快太赫兹工程。