(Sub)nanoscale hyperspectral imaging of excitons in two-dimensional materials

Quantum emitter lattices in the form of excitons (electron-hole pairs) can create technical breakthroughs in the area of quantum computing and sensing applications. It is challenging to have (long) short-range ordered excitons in solid state systems due to complexities in delocalization and materials imperfections. Moiré transition metal dichalcogenides (TMD) are predicted to be the most promising material platforms to engineer ordered and reconfigurable quantum emitter exciton lattices due to topological structural reconstruction and flat band formation. However, the corresponding metrology tools to “see” these quantum emitter lattices experimentally at a single moiré supercell level are lacking. In this talk, I will highlight how we use low-loss scanning transmission electron microscopy-electron energy loss spectroscopy to image excitons at (sub)nanoscale. At the end of my talk, I will also highlight some of the technical challenges that can inhibit the imaging of excitons.