Tip-enhanced Raman spectroscopy (TERS) with sub-nanometer spatial resolution has been recently demonstrated experimentally. However, the physical mechanism underlying is still under discussion. Here, we theoretically investigate the electric field gradient of a coupled tip-substrate system. Our calculations suggest that the ultra-high spatial resolution of TERS can be partially attributed to the electric field gradient effect owning to its tighter spatial confinement and sensitivity to the infrared (IR)-active of molecules.
@article{arxiv.1411.2691,
title = {Effects of Electric Field Gradient on Sub-nanometer Spatial Resolution of Tip-enhanced Raman Spectroscopy},
author = {Lingyan Meng and Zhilin Yang and Jianing Chen and Mengtao Sun},
journal= {arXiv preprint arXiv:1411.2691},
year = {2015}
}