| dc.description.abstract | Tip-enhanced Raman scattering (TERS) and tip-enhanced photoluminescence (TEPL) can be widely applied to multi-disciplinary studies involving near-field scanning technologies. Several types of TERS setups have been applied in fields including biosensing, high-resolution imaging, and photocatalysis. After 20 years of development, TERS has been improved to resolve sub-nanometer structures with a high enhancement factor at 10^13 over traditional Raman scattering. Furthermore, due to the quantum plasmonic effects, the tip-molecule interactions play a significant role during TERS measurements. In this dissertation, we will discuss the applications of TERS and TEPL in both the classical and quantum ways. In the classical regime, where the tip-molecule interactions are less important, we introduce our efforts to achieve bioimaging at sub-nanometer resolution. So as to understand the essential mechanisms, we introduce an innovative model of tip-substrate cavities and discuss several distinct enhancement scenarios. On the other hand, in the quantum regime, where charge transfer effects are unavoidable, we work out a theoretical model involving the charge transfer and apply it to study and control photoelectrical properties of 2D semiconductors. Consequently, this dissertation summarizes the overall properties of TERS, for the purpose of classifying different regimes and extending the applications to multidisciplinary branches of biophysics and biochemistry. | en |
