@article{Li2023, 
author = {Shaobo Li and Fei Wang and Ze Zhang and Shuhao Zhao and Chengsheng Xia and Peirui Ji and Xiaomin Wang and Guofeng Zhang and Tao Liu and Feng Chen and Shuming Yang},
title = {Polarization-insensitive plasmon nanofocusing with broadband interference modulation for optical nanoimaging},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {7},
pages = {9990-9996},
keywords = {near-field scanning optical microscopy, azimuthal asymmetries, plasmonic nanoconcentrator, fiber-based plasmonic tip},
url = {https://www.sciopen.com/article/10.1007/s12274-023-5525-1},
doi = {10.1007/s12274-023-5525-1},
abstract = {Delivering light to the nanoscale using a flexible and easily integrated fiber platform holds potential in various fields of quantum science and bioscience. However, rigorous optical alignment, sophisticated fabrication process, and low spatial resolution of the fiber-based nanoconcentrators limit the practical applications. Here, a broadband azimuthal plasmon interference nanofocusing technique on a fiber-coupled spiral tip is demonstrated for fiber-based near-field optical nanoimaging. The spiral plasmonic fiber tip fabricated through a robust and reproducible process can reverse the polarization and modulate the mode field of the surface plasmon polaritons in three-dimensionally azimuthal direction, resulting in polarization-insensitive, broad-bandwidth, and azimuthal interference nanofocusing. By integrating this with a basic scanning near-field optical microscopy, a high optical resolution of 31 nm and beyond is realized. The high performance and the easy incorporation with various existing measurement platforms offered by this fiber-based nanofocusing technique have great potential in near-field optics, tip-enhanced Raman spectroscopy, nonlinear spectroscopy, and quantum sensing.}
}