Magnetic plasmon resonances in nanostructured topological insulators for strongly enhanced light–MoS2 interactions

Abstract

Topological insulators: visible range magnetic resonances Nanostructured antimony telluride (Sb2Te3) can support visible range magnetic resonances and dramatically enhance the weak interactions of light with 2D materials. Hua Lu and workers from China and Australia used focused ion beam milling to write a grating of periodic nanogrooves into single-crystalline Sb2Te3, a well-known topological insulator. They then placed a flake of the 2D material MoS2 on top. Characterization showed the existence of a kind of magnetic plasmon resonances (MPRs) with a resonant wavelength that redshifts with increasing nanogroove height and pitch and blueshifts with increasing nanogroove width. Visible photoluminescence experiments showed that the MPRs can dramatically increase the emission from the MoS2, which could be tuned by changing the polarization angle of the incident excitation light. The findings are expected to aid the development of nanoscale optical devices made from layered nanomaterials.