Twist-angle Control of Nonlinear Interference in a ZnO Nanowire/Monolayer WSe$_2$ Hybrid Structure

Abstract

Nanoscale devices that integrate materials of different dimensionalities (0D, 1D, and 2D) hold great potential for advanced applications in photonics and optoelectronics. A fundamental requirement for the development of such devices is the engineering and control of light-matter interactions beyond the simple enhancement or quenching of linear and nonlinear optical emission. In this study, we demonstrate control over nanoscale light-matter interactions by achieving twist-angle tunability of the nonlinear optical response in a hybrid system composed of a ZnO nanowire and a monolayer of WSe$_2$. By varying the relative orientation between the ZnO polar axis and the WSe$_2$ crystal axes, we realize both constructive and destructive interference in second-harmonic generation, as well as full material selectivity in second harmonic polarization-dependent measurements. These outcomes arise from the distinct dimensionalities and symmetries of the hybrid constituents, underscoring the generality of our approach. Thus, our work presents an advanced framework for the design and control of nonlinear light-matter interactions in nanoscale hybrid devices, thereby paving the way for their future use in photonic and optoelectronic technologies.