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arXiv · 2307.00275

Terahertz spin currents in nanoscale spatial resolution

Jiahua Cai·Mingcong Dai·Sai Chen·Peng Chen·Jiaqi Wang·Hongting Xiong·Zejun Ren·Shaojie Liu·Zhongkai Liu·Caihua Wan·Xiaojun Wu
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Abstract

The ability to generate, detect, and control coherent terahertz (THz) spin currents with femtosecond temporal and nanoscale spatial resolution has significant ramifications. The diffraction limit of concentrated THz radiation, which has a wavelength range of 5 {\mu}m-1.5 mm, has impeded the accumulation of nanodomain data of magnetic structures and spintronic dynamics despite its potential benefits. Contemporary spintronic optoelectronic apparatuses with dimensions 100 nm presented a challenge for researchers due to this restriction. In this study, we demonstrate the use of spintronic THz emission nanoscopy (STEN), which allows for the efficient injection and precise coherent detection of ultrafast THz spin currents at the nanoscale. Furthermore, STEN is an effective method that does not require invasion for characterising and etching nanoscale spintronic heterostructures. The cohesive integration of nanophotonics, nanospintronics, and THz-nano technology into a single platform is poised to accelerate the development of high-frequency spintronic optoelectronic nanodevices and their revolutionary technical applications.

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Jiahua Cai, Mingcong Dai, Sai Chen, Peng Chen, Jiaqi Wang, Hongting Xiong, Zejun Ren, Shaojie Liu, Zhongkai Liu, Caihua Wan, Xiaojun Wu. 2023-07-01. Terahertz spin currents in nanoscale spatial resolution. https://arxiv.org/abs/2307.00275

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