Near-Field Optical Study of 2D Semiconductors

Two-dimensional semiconductors have been attractive recently due to their novel physical (e.g., optoelectronic, valleytronic and mechanical) properties in a single or few atomic layers. Scanning near-field optical microscopy (SNOM) provides an exciting avenue to study those novel 2D materials with high spatial resolution. For example, zero and one-dimensional features or physical processes, including local defects or domain boundaries, can be imaged, which provides unique physics insights. In this talk we will focus on a few progresses on exciton inhomogeneity mapping by near-field photoluminescence spectroscopy and microscopy.