论文标题
在中红外等离激元天线的第二次谐波生成中的巨型磁反应效应
Giant Magneto-refractive Effect in Second Harmonic Generation from Plasmonic Antennas in the Mid-infrared
论文作者
论文摘要
金属纳米结构在表面等离子体共振下表现出强烈的非线性响应，其中光 - 偶联效率提高了。可以通过外部磁场来实现此响应的主动调制。在这里，我们在Spintronic多层天线中利用非线性磁反射效应来实现中红外第二次谐波生成（SHG）的共振20 \％调制。我们讨论了该调制的机制，并表明它不能通过多层旋转状态中电磁场的不相等增强来解释。取而代之的是，我们提出了对非线性敏感性的新颖贡献，该敏感性依赖于金属中的自旋依赖性电子平均自由路径。与铁磁体中的磁性磁磁体相反，我们的方法不会导致共振的转移，因此可以同时观察到最大的SHG及其最强的调制。
Metallic nanostructures exhibit strong nonlinear-optical response at surface plasmon resonances, where the light-matter coupling efficiency is enhanced. An active modulation of this response can be realized by means of an external magnetic field. Here we utilize a nonlinear magneto-refractive effect in spintronic multilayer antennas to achieve a resonant 20\% modulation in second harmonic generation (SHG) in the mid-infrared. We discuss mechanisms of this modulation and show that it cannot be explained by an unequal enhancement of the electromagnetic field in the two spin states of the multilayer. Instead, we propose a novel contribution to the nonlinear susceptibility, which relies on the spin-dependent electron mean free path in metals. In contrast to magneto-optics in ferromagnets, our approach results in no shift of the resonance and thus ensures that the largest SHG and its strongest modulation are simultaneously observed.
