A structure that enhances light absorption in two-dimensional transition metal sulfides

Abstract

The present invention discloses a structure with a light absorption-enhanced two-dimensional transition metal sulfide. The structure mainly comprises a substrate, a distributed Bragg reflector (DBR), the two-dimensional transition metal sulfide and a precious metal nano grating; the DBR is composed of two different dielectric layers of different refractive indexes; the refractive indexes and thicknesses of the dielectric layers can be adjusted, so that the absorption of light of a specified band by the two-dimensional transition metal sulfide can be enhanced; and the periodic metal nano grating is prepared on the surface of the two-dimensional transition metal sulfide, and therefore, the metal nano grating, on the one hand, can diffuse light which is not absorbed by the two-dimensional material and is reflected by the DBR, and on the other hand, forms local surface plasmon resonance with incident light so as to realize near-field enhancement. According to the structure of the invention, the light absorption of the two-dimensional transition metal sulfide is significantly enhanced.

Description

Technical field: [0001] The invention belongs to the field of optoelectronic technology and relates to a structure for enhancing light absorption of two-dimensional transition metal sulfides. Background technique: [0002] The chemical formula of two-dimensional transition metal sulfide is MX 2 , M refers to transition metal elements (for example: molybdenum, tungsten, niobium, rhenium, titanium), and X refers to chalcogen elements (for example: sulfur, selenium, tellurium). Generally, a single-layer transition metal sulfide exhibits an X-M-X sandwich structure. The van der Waals force between the layers of the structure is very weak, but there are strong covalent bonds in the plane. Therefore, the bulk transition metal sulfide can be exfoliated into single-layer or multi-layer nanosheets and applied to various devices. [0003] In recent years, two-dimensional transition metal sulfides have attracted wide attention from many scientists due to their unique electrical and optical p...

AI Technical Summary

Problems solved by technology

However, due to their ultrathin material properties, 2D transition metal dichalcogenides have low light absorption, which limits their applications in high-performance optoelectronic devices such as solar energy conversion devices and photodetectors.

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