Xing Qiaoxia, Song Chaoyu, Wang Chong, Xie Yuangang, Huang Shenyang, Wang Fanjie, Lei Yuchen, Yuan Xiang, Zhang Cheng, Mu Lei, Huang Yuan, Xiu Faxian, Yan Hugen
State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China.
Key Laboratory of Micro and Nano-Photonic Structures (Ministry of Education), Fudan University, Shanghai 200433, China.
Phys Rev Lett. 2021 Apr 9;126(14):147401. doi: 10.1103/PhysRevLett.126.147401.
Tunable terahertz plasmons are essential for reconfigurable photonics, which have been demonstrated in graphene through gating, though with relatively weak responses. Here we demonstrate strong terahertz plasmons in graphite thin films via infrared spectroscopy, with dramatic tunability by even a moderate temperature change or an in situ bias voltage. Meanwhile, through magnetoplasmon studies, we reveal that massive electrons and massless Dirac holes make comparable contributions to the plasmon response. Our study not only sets up a platform for further exploration of two-component plasmas, but also opens an avenue for terahertz modulation through electrical bias or all-optical means.
可调谐太赫兹等离子体激元对于可重构光子学至关重要，其已通过石墨烯中的门控得以实现，不过响应相对较弱。在此，我们通过红外光谱在石墨薄膜中展示了强太赫兹等离子体激元，通过适度的温度变化或原位偏置电压即可实现显著的可调谐性。同时，通过磁等离子体激元研究，我们揭示了大量电子和无质量狄拉克空穴对等离子体激元响应的贡献相当。我们的研究不仅为进一步探索双组分等离子体搭建了平台，还为通过电偏置或全光手段进行太赫兹调制开辟了道路。
