By developing a bidirectional-pump terahertz (THz) emission spectroscopy, we reveal an anomalous Nernst effect (ANE) induced THz emission in a single ferromagnetic film. Based on the distinctive symmetry of the THz signals, ANE is unequivocally distinguished from the previously attributed ultrafast demagnetization and anomalous Hall effect mechanisms. A quantitative method is established to separate the different contributions, demonstrating a significant ANE contribution that even overwhelms other competing mechanisms. Our work not only clarifies the origin of the ferromagnetic-based THz emission, but also offers a fertile platform for investigating the ultrafast magnetism and THz spintronics.
@article{arxiv.2302.11134,
title = {Anomalous Nernst effect induced terahertz emission in a single ferromagnetic film},
author = {Zheng Feng and Wei Tan and Zuanming Jin and Yi-Jia Chen and Zhangfeng Zhong and Liang Zhang and Song Sun and Jin Tang and Yexing Jiang and Po-Hsun Wu and Jun Cheng and Bingfeng Miao and Haifeng Ding and Dacheng Wang and Yiming Zhu and Liang Guo and Sunmi Shin and Guohong Ma and Dazhi Hou and Ssu-Yen Huang},
journal= {arXiv preprint arXiv:2302.11134},
year = {2023}
}