Mass Fabrication of WS2 Nanodisks and their Scattering Properties

High-index all-dielectric resonators have been developed into an important platform for light manipulation at the nanoscale over the past decade. Although they are widely used as 2D materials, transition metal dichalcogenides (TMDCs), as an emerging all-dielectric material, have also been used to fabricate optical nanoantennas that support multipolar Mie resonances. However, their fabrication depends heavily on electron-beam lithography (EBL) or focused ion beam (FIB), which is expensive and time-consuming for practical applications. To address this issue, here, a fast low-cost method is put forward which combines polystyrene (PS) nanospheres with physical vapor deposition by electron-beam evaporation and magnetron sputtering to fabricate WS2 nanodisks in a mass-production manner. After annealing, the A- and B-exciton features as well as anapole states are observed in the scattering spectra of WS2 nanodisks. The light scattering anisotropy of individual WS2 nanodisks and spectral tunability of the anapole are studied. In addition, absorption enhancement due to the strong field localization of anapole states in hexagonal WS2 nanodisk arrays is numerically demonstrated. This work manifests that this etching-free method is promising for fabrication of scalable TMDC nanodisks suitable for practical applications.