PtS₂ metamaterials: Fabrication and physical properties

Metamaterials are electromagnetic materials with engineered sub-wavelength structures, which can be coupled with the incident electromagnetic wave to produced peculiar physical properties. Currently, many studies are being conducted to the transition metal dichalcogenides (TMDs) due to their unique structures and novel physical properties. Here, we produced honeycomb nanostructure with various sizes on few-layer PtS₂ through a well-developed nanosphere lithography technology. In this way, the unique properties of PtS₂ metamaterials can be tuned to explore more exotic physical characteristics. The honeycomb surface morphology of PtS₂ metamaterials has been demonstrated using the scanning electron microscope and the atomic force microscope. The optical absorption spectra of Pt and PtS₂ metamaterials were investigated and the results show that the absorption spectra can be modulated by changing the size of the nanostructure. In addition, the optical anisotropic properties of Pt and PtS₂ metamaterials were characterized through the angle-resolved absorption spectra. Raman spectroscopy shows the surface-enhanced Raman spectroscopy (SERS) effect of Pt metamaterials. The simulation exhibits the electric field distribution of PtS₂ metamaterials at different wavelengths. The results offer a new approach to develop novel optoelectronic devices based on the meta-structure of TMDs.