Most of information we, humans, receive is the visual information. Not only we learn about the world using the images, it helps us to make models and think. Utilizing specialized imaging techniques for understanding physics of materials is a task with a long history. However, when coming to studying properties of novel nanoscale materials, for example, heteronanotubes, graphene, TMDCs, MXenes and 2d atomic polar metals, one has to give up the versatility and power of optical characterization methods – due to diffraction limited resolution of optics – unless some approach is invented to beat the diffraction limit.

In this talk, I will touch on scattering Scanning Near-field Optical Microscopy (sSNOM) as a nanoscale optical characterization method. Correlated optical (mid-IR) imaging technique will be introduced using examples of twisted graphene and 2d polar metals.  sSNOM will be shown to map polaritonic wavefunctions. The new method will be introduced to directly extract polariton dispersion from the experimental data. Finally, I will discuss the polaritonic confinement in plasmonic heterostructures of 2d polar metals and the theory of non-linear polaritonic standing waves.

Acknowledgement: partial support from NSF CHE-2032582, CHE-2032601, DMR-1539916 and DMR-2011839.