Electric and magnetic terahertz nonlinearities resolved on the sub-cycle scale
Electric and magnetic terahertz nonlinearities resolved on the sub-cycle scale
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DOI：
10.1088/1367-2630/15/6/065003
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发表时间：
2013-06
影响因子：
3.3
通讯作者：
A. Pashkin;A. Sell;T. Kampfrath;R. Huber
中科院分区：
文献类型：
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作者：
A. Pashkin;A. Sell;T. Kampfrath;R. Huber
桌面源的强烈多太赫兹（THz）脉冲打开了大门，在以前难以捉摸的中，远红外光谱制度的极端非线性的研究。讨论了锁相太赫兹脉冲与凝聚态物质全相干耦合的两个概念。第一种方法演示了半导体材料InSb的二维多太赫兹光谱。通过对非线性光学响应的相位和振幅敏感检测，我们能够将非相干泵浦-探测信号与相干四波混频分离，并揭示出非常非微扰的非线性。虽然这类相互作用是由太赫兹脉冲的电场分量介导的，但第二种方法是互补的，因为它表明，或者，可以利用太赫兹磁场来选择性地控制反铁磁NiO中的自旋自由度。
Table-top sources of intense multi-terahertz (THz) pulses have opened the door to studies of extreme nonlinearities in the previously elusive mid- to far-infrared spectral regime. We discuss two concepts of fully coherent coupling of phase-locked THz pulses with condensed matter. The first approach demonstrates two-dimensional multi-THz spectroscopy of the semiconductor material InSb. By phase- and amplitude-sensitive detection of the nonlinear optical response, we are able to separate incoherent pump–probe signals from coherent four-wave mixing and reveal extremely non-perturbative nonlinearities. While this class of interactions is mediated by the electric field component of the THz pulse, the second approach is complementary, as it demonstrates that, alternatively, the magnetic THz field may be exploited to selectively control the spin degree of freedom in antiferromagnetic NiO.