Nanoimaging of surface waves in 2D materials

Propagating surface waves such as surface-plasmon polaritons and exciton-polaritons have recently been of interest in a variety of optical, electronic and quantum communication applications. Nano-optical imaging of surface waves in two-dimensional (2D) transition-metal dichalcogenide (TMD) materials has been realized in several cavity-coupled systems. In this work, new nanoimaging schemes based on tip-enhanced photoluminescence (TEPL) and Kelvin-probe force microscopy (KPFM) are presented, revealing the optical and electric components of surface waves in 2D TMD heterostructures, respectively. These results could be used in novel nanophotonic coupling schemes for quantum emitters in 2D materials.