Interacting Light with Semiconductor at the Nanoscale

The ability to probe and control light-matter interaction at the nanometer scale not only advances frontiers of fundamental science, but also is a critical prerequisite to device applications in electronics, sensing, catalysis, energy harvesting, and more. Exploiting and enhancing the originally weak light-matter interactions via nanofabricated photonic structures; we will be able to sense chemical species at single molecule levels, to devise better imaging and manufacturing tools, to transfer data more efficiently at higher speed.

In this talk, I will first describe a simple and general nano-optical device developed during my Ph.D., called campanile probe, which lay groundwork for generally-applicable nano-optical studies. Two examples will be discussed, where we cross the boundary from insufficient to sufficient resolution beyond optical diffraction limit and perform optical hyperspectral imaging of luminescence heterogeneity along InP nanowires and synthetic monolayer MoS₂, providing spectral information distinct from diffraction limited micro-PL spectral imaging. Following this, I will discuss the recent works using cavities to further enhance the strength of light-matter interaction into the strong coupling regime. The formation of coherently coupled cavity exciton-polariton in two-dimensional monolayer WS₂ and the inorganic perovskite CsPbBr₃ as well as the ultralow threshold optically pumped polariton lasing in perovskite cavities will be shown. Finally, I will conclude by presenting my vision of how these devices can enable a wide range of capabilities with relevance to multidimensional spectroscopy imaging, efficient solid-state lighting and even beyond.