Terahertz waveform sampling under scanning tunneling microscope

Tianwu Wang1,2,3,4, Hongbo Li1,2,3,4, Guangyou Fang1,2,3,4, and Yirong Wu1,2,3,4

1GBA branch of Aerospace Information Research Institute, Chinese Academy of Sciences, Guangzhou 510700, China
2Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China
3School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
4Guangdong Provincial Key Laboratory of Terahertz Quantum Electromagnetics, Guangzhou 510700, China

Terahertz (THz) wave is between microwave and far-infrared, THz spectroscopy has become a novel method to study physics, material science, biomedical science, et al. Due to the diffraction limit, the spatial resolution of THz imaging in far field is normally limited to be hundreds of micrometers. THz scanning tunneling microscope (THz-STM) has been developed as a novel technique, combining both sub-picosecond temporal resolution and atomic spatial resolution. With a scanning metal tip, the resolution can be down to sub-nanometer scale. In the talk, I will present our recent progress on high spatial and temporal THz scanning tunneling microscope, including how to control THz Carrier-Envelope Phase to coherently control the tunneling electrons [1] and sampling THz waveform under the metal tip [2]. In addition, I will introduce ultrafast laser-based THz research systems in our new lab.

Figure 1: (a) THz waveform sampling under metal tip of scanning tunnelling microscope. (b) THz time-domain waveforms with different Carrier-Envelope Phase controlled by a metamaterial device.

[1] T. Li, B. Quan, G. Fang, T. Wang, “Flexible THz Carrier-Envelope Phase Shifter Based on Metamaterials”. Adv. Optical Mater. 10, 2200541 (2022);
[2] H. Li, T. Wang, W. Wei, K. Zhang, J. Xu, Y. Wu, G. Fang, “Real-space sampling of terahertz waveforms with sub-nanometer spatial resolution”; arXiv:2310.17524

Scroll to Top