基于超快自旋电子学太赫兹发射源的研究与应用

Terahertz(THz) technology has shown great research potential and application value in biosensing, microscopic imaging, wireless communication, nondestructive testing and other fields. However, one of the bottlenecks restricting the rapid development of THz technology is the lack of high efficiency, high integration, low power consumption and easily modulated THz emitters. The THz radiation generated by spintronic terahertz emitter(STE) based on the ultrafast spin to charge conversion in ferromagnetic/non-magnetic heterostructure has the advantages of wide frequency band, low cost, easy fabrication and high field intensity, which has attracted the interest of many scholars at home and abroad in recent years. In this paper, the THz emission mechanism based on ultrafast spin dynamics are briefly introduced. And the feasible schemes to regulate and optimize its efficiency are further analyzed and reviewed. Furthermore, the new emission mechanisms and application prospects of STE are analyzed. New emission mechanisms include the emission of spintronic THz with different chirality and polarization states, and the exploration of STE based on new-type materials. And application prospects include spintronic THz spectroscopy, spintronic THz imaging and spintronic THz emission-regulation integration technology. Finally, the paper is summarized, and the future improvement, exploration and application of ultrafast spintronic terahertz emission sources, as well as the microscopic mechanism of spintronics driven by terahertz electromagnetic pulse are prospected.