State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, China.
State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.
Phys Rev Lett. 2018 Aug 24;121(8):086801. doi: 10.1103/PhysRevLett.121.086801.
Novel mechanisms for electromagnetic wave emission in the terahertz frequency regime emerging at the nanometer scale have recently attracted intense attention for the purpose of searching next-generation broadband THz emitters. Here, we report broadband THz emission, utilizing the interface inverse Rashba-Edelstein effect. By engineering the symmetry of the Ag/Bi Rashba interface, we demonstrate a controllable THz radiation (∼0.1-5 THz) waveform emitted from metallic Fe/Ag/Bi heterostructures following photoexcitation. We further reveal that this type of THz radiation can be selectively superimposed on the emission discovered recently due to the inverse spin Hall effect, yielding a unique film thickness dependent emission pattern. Our results thus offer new opportunities for versatile broadband THz radiation using the interface quantum effects.
最近，人们对在纳米尺度上出现的太赫兹频率范围内的电磁波发射新机制产生了浓厚的兴趣，以期寻找下一代宽带太赫兹发射器。在这里，我们报告了利用界面反拉什巴-埃德斯坦效应实现的宽带太赫兹发射。通过工程化 Ag/Bi 拉什巴界面的对称性，我们展示了一种可控制的太赫兹辐射（∼0.1-5 太赫兹）波形，该波形是在光激发后从金属 Fe/Ag/Bi 异质结构中发射出来的。我们进一步揭示了这种类型的太赫兹辐射可以选择性地叠加在由于逆自旋霍尔效应而最近发现的发射上，从而产生独特的随膜厚变化的发射模式。因此，我们的研究结果为利用界面量子效应实现多功能宽带太赫兹辐射提供了新的机会。
