Optical Stark Effect of a Single Defect on TiO2(110) Surface
Abstract
Probing optical Stark effect at the single-molecule or atomic scale is crucial for understanding many photo-induced chemical and physical processes on surfaces. Here we report a study about optical Stark effect of single atomic defects on TiO2(110) surface with photo-assisted scanning tunneling spectroscopy. When a laser is coupled into the tunneling junction, the mid-gap state of OH-O2 defects changes remarkably in the differential conductance spectra. As laser power gradually increases, the energy of the mid-gap state shifts away from the Fermi level with increase in intensity and broadening of peak width. The observation can be explained as optical Stark effect with the Autler-Townes formula. This large optical Stark effect is due to the tip-enhancement and the strong dipole moment in the transient charged state during electron tunneling. Our study provides new aspects in exploring electron-photon interactions at the microscopic scale.
Cite
@article{arxiv.1807.08457,
title = {Optical Stark Effect of a Single Defect on TiO2(110) Surface},
author = {Lihuan Sun and Anning Dong and Jianmei Li and Dong Hao and Xiangqian Tang and Shichao Yan and Yang Guo and Xinyan Shan and Xinghua Lu},
journal= {arXiv preprint arXiv:1807.08457},
year = {2018}
}
Comments
13 pages, 4 figures