Novel nonrelativistic and nonmagnetic control of terahertz charge currents via electrical anisotropy in conductive materials

报告人: 陶镇生 (复旦大学)

报告时间: 2023年4月25日 10:00

报告地点: 理科楼C302

报告摘要:Precise and ultrafast control over photo-induced charge currents across nanoscale interfaces could lead to important applications in energy harvesting, ultrafast electronics, and coherent terahertz sources. In this talk, I will introduce recent developments in terahertz emitters based on spintronic devices utilizing several relativistic mechanisms, including inverse spin-Hall effect, inverse Rashba-Edelstein effect and inverse spin-orbit-torque effect. I will also present a novel nonrelativistic and nonmagnetic mechanism that directly utilizes the photo-excited high-density charge currents across the interface. We demonstrate that the electrical anisotropy of conductive materials can effectively deflect injected charge currents to the transverse direction, resulting in efficient and broadband terahertz radiation. Importantly, this new mechanism has the potential to offer an order of magnitude higher conversion efficiency compared to previous methods. Our new findings offer exciting possibilities for directly utilizing these photo-excited high-density currents across metallic interfaces for ultrafast electronics and terahertz spectroscopy.