CEA-DAM, DIF, 91297 Arpajon, France.
Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany and Institute of Condensed Matter Theory and Optics, Friedrich Schiller University, 07743 Jena, Germany.
Phys Rev Lett. 2013 Feb 15;110(7):073901. doi: 10.1103/PhysRevLett.110.073901.
Terahertz (THz) radiation produced by the filamentation of two-color pulses over long distances in argon is numerically investigated using a comprehensive model in full space-time-resolved geometry. We show that the dominant physical mechanism for THz generation in the filamentation regime at clamping intensity is based on quasi-dc plasma currents. The calculated THz spectra for different pump pulse energies and pulse durations are in agreement with previously reported experimental observations. For the same pulse parameters, near-infrared pump pulses at 2 μm are shown to generate a more than 1 order of magnitude greater THz yield than pumps centered at 800 nm.
太赫兹（THz）辐射是通过在氩气中双色脉冲的细丝化远距离产生的，我们使用全时空分辨几何的综合模型对其进行了数值研究。我们表明，在箝位强度的细丝化区域中产生 THz 的主要物理机制基于准直流等离子体电流。不同泵浦脉冲能量和脉冲持续时间的计算 THz 光谱与之前报道的实验观察结果一致。对于相同的脉冲参数，2μm 的近红外泵浦脉冲比中心波长为 800nm 的泵浦脉冲产生的 THz 辐射强度高出一个数量级以上。
