Topological insulator behavior of WS2 monolayer with square-octagon ring structure
نویسندگان
چکیده
We report electronic behavior of an allotrope of monolayer WS2 with a square octagon ring structure, refereed to as (so-WS2) within state-of-the-art density functional theory (DFT) calculations. TheWS2 monolayer shows semi-metallic characteristics with Dirac-cone like features around Г. Unlike p-orbital’s Dirac-cone in graphene, the Dirac-cone in the so-WS2 monolayer originates from the d-electrons of the W atom in the lattice. Most interestingly, the spin-orbit interaction associated with d-electrons induce a finite band-gap that results into the metal-semiconductor transition and topological insulator-like behavior in the so-WS2 monolayer. These characteristics suggest the so-WS2 monolayer to be a promising candidate for the next-generation electronic and spintronics devices.
منابع مشابه
Topological insulating states in 2D transition metal dichalcogenides induced by defects and strain.
First-principles calculations and extensive analyses reveal that the H phase of two-dimensional (2D) transition metal dichalcogenides (TMDs) can be tuned to topological insulators by introducing square-octagon (4-8) defects and by applying equi-biaxial tensile strain simultaneously. The 2D structure composed of hexagonal rings with 4-8 defects, named sho-TMD, is dynamically and thermally stable...
متن کاملDesign and Simulation of a Metal-Insulator-Metal Filter Based on Plasmonic Split Ring
In this paper, a plasmonic filter made of a split ring, two U-shaped structures and two straight waveguides is designed and investigated. In the proposed structure, the split ring and U-shaped structures are situated between straight waveguides. Simulations are done based on FDTD method. Split ring, U-shaped structures and straight waveguides are made of air in the silver background. In the pro...
متن کاملBackscattering in silicon photonic devices
We report on the backscattering induced by sidewall roughness in silicon on insulator optical nanowires, its dependence on the waveguide geometrical and optical parameters and its impact on silicon photonic devices. In silicon ring resonators cavity-enhanced backscattering, increasing with the square of the resonator’s finesse, emerges as a severe
متن کاملBand topology and quantum spin Hall effect in bilayer graphene
We consider bilayer graphene in the presence of spin orbit coupling, to assess its behavior as a topological insulator. The first Chern number n for the energy bands of single and bilayer graphene is computed and compared. It is shown that for a given valley and spin, n in a bilayer is doubled with respect to the monolayer. This implies that bilayer graphene will have twice as many edge states ...
متن کاملMixed multilayered vertical heterostructures utilizing strained monolayer WS2.
Creating alternating layers of 2D materials forms vertical heterostructures with diverse electronic and opto-electronic properties. Monolayer WS2 grown by chemical vapour deposition can have inherent strain due to interactions with the substrate. The strain modifies the band structure and properties of monolayer WS2 and can be exploited in a wide range of applications. We demonstrate a non-aque...
متن کامل