LIGHT-MATTER INTERACTION IN 2D SEMICONDUCTORS AND PHOTONIC DEVICE IMPLEMENTATION

Abstract

In recent years, there has been significant research interest in two-dimensional (2D) layered materials due to their unique physical properties. Among these materials, InSe stands out as a promising 2D semiconductor. This thesis investigates various aspects of InSe in different contexts. Firstly, we examine the photocurrent generation mechanisms in encapsulated few-layer InSe phototransistors. Our findings indicate that the photogating effect largely governs the general photoresponse, particularly noting a significant superlinear dependence of photocurrent on excitation power under large, negative gate voltage conditions. Additionally, we explore momentum-matched interlayer excitons (IX) in WS₂/InSe heterostructures, where our findings suggest other possible influential factors beyond momentum-matching that may contribute to strong IX emissions. Lastly, we demonstrate the mode-center placement of a 2D heterostructure (WS₂/hBN) within a newly-developed elastomer ridge waveguide, The improved material-waveguide coupling and polarization-dependent capabilities offer new opportunities for exploring flexible hybrid-photonic devices.