Near-field nanoimaging of biological cells on 2D materials

Abstract

Two-dimensional (2D) semiconducting materials such as transition metal dichalcogenides (TMDs) have been widely investigated for the potential use in optoelectronic, biosensing and photovoltaic applications. Nanoscale heterogeneous morphological, electronic and optical properties of these materials play a crucial role in the device performance. We use tip-enhanced Raman and photoluminescence near-field nanoimaging techniques to better understand the materials and hybrid biological systems such as bacterial and cancer cells on 2D TMDs and lateral heterostructures. We investigate the effects of local strain, doping, hot electron injection and transfer, as well as the electromagnetic and chemical enhancement mechanisms in these systems. The results show unusual tip-sample interaction effects that could reveal new synergistic phenomena at the nano- and picometer scales.