Nanoscale Spatially Resolved Terahertz Response of a PbS-Graphene Heterostructure
Heterostructures have promising applications in photonics and optoelectronics, mainly due to their high electron mobility and broadband photoresponse covering visible, infrared, and terahertz (THz) ranges. However, it is challenging to detect heterostructures in high definition with conventional THz techniques. Here we demonstrate a THz nanoscopic imaging method which is capable of resolving the local THz response of PbS-graphene heterostructures based upon a sophisticated THz near-field optical microscope. The interaction between the THz near field and the heterostructure is further explored by numerical simulations. The results reveal that both the composition and structure of the layers composing the heterostructure contribute to the THz signal. Furthermore, we develop a reliably finite dipole model suitable for retrieving THz optoelectronic properties of multilayered systems from measured THz hyperspectra, and realize mapping the local effective permittivity and conductivity of the heterostructure. Our work discloses the mechanism of the THz response of heterostructures, and provides a useful method for high-definition quantifying complex THz materials and devices.
Authors
- Yunchang Guo (ORCID: https://orcid.org/0000-0001-5519-2570)
- Qihua Xiong (ORCID: https://orcid.org/0000-0002-2555-4363)
- Fucheng Qiu (ORCID: https://orcid.org/0000-0003-3927-7966)
- Jiaguang Han (ORCID: https://orcid.org/0000-0001-9425-9635)
- Ligang Chen (ORCID: https://orcid.org/0000-0002-4231-8821)
- Hua Li (ORCID: https://orcid.org/0000-0003-3689-2437)
- Shuanglong Feng (ORCID: https://orcid.org/0000-0003-3910-4600)
- Zhen Tian (ORCID: https://orcid.org/0000-0002-2861-4325)
- Chan Yang (ORCID: https://orcid.org/0000-0001-5768-0615)
- Min Hu (ORCID: https://orcid.org/0000-0001-6214-4147)
- Zhongbo Yang
- Huabin Wang
- Zhiming Huang
Institutions
- University of Electronic Science and Technology of China (CN)
- Tianjin University (CN)
- Zomega Terahertz (United States) (US)
- Dynamic Imaging (United Kingdom) (GB)
- Chongqing Institute of Green and Intelligent Technology (CN)
- Shanghai Institute of Technical Physics (CN)
- Shanghai Institute of Microsystem and Information Technology (CN)
- Infrared Laboratories (United States) (US)
- Spectrum Research (United States) (US)
- University of Chinese Academy of Sciences (CN)
- Tsinghua University (CN)
Publication Details
- Journal
- ACS Nano
- Published
- 2025-03-11
- DOI
- https://doi.org/10.1021/acsnano.4c16185
- Citations
- 5
- Primary Topic
- Photonic Crystals and Applications
- Type
- article
- Field-Weighted Citation Impact
- 6.23
Funders
- National Natural Science Foundation of China
- Natural Science Foundation of Chongqing
- University of Chinese Academy of Sciences
- National Key Research and Development Program of China