The interaction of light and matter at the nanoscale is an important aspect of nanophotonics. The nano-resonant system allows scientists to control and increase electromagnetic energy in a volume smaller than the wavelength of the incident light. As well as allowing sunlight to be captured much more effectively, they also facilitate better optical wave guidance and emission control.
The strong coupling of light with electronic excitation in solid materials results in hybridized photonic and electronic states, called polaritons, which can exhibit interesting properties such as Bose-Einstein condensation and superfluidity.
A new study, published in the journal Natural Ingredients, presenting advances in the fusion of light and matter at the nanoscale. Researchers led by LMU physicist Dr. Andreas Tittl has developed a metasurface that allows for strong coupling effects between light and transition metal dichalcogenides (TMDCs). This novel platform is based on a photonic bound state in the continuum, called BIC, in the nanostructured tungsten disulfide (WS2). The simultaneous utilization of WS2 as a base material for the fabrication of sharp resonance metasurfaces and as a coupling partner that supports the excitation of the active ingredient opens up new possibilities for research into polaritonic applications.
An important breakthrough in this research is to control the coupling strength, which is independent of material losses. As the metasurface platform is able to seamlessly integrate other TMDC or excitonic materials, it can provide fundamental insights and practical device concepts for polaritonic applications. Additionally, the newly developed metasurface concept provides a foundation for applications in controllable low-threshold semiconductor lasers, photocatalytic enhancement, and quantum computing.