We study how an electric field induces a topological phase transition in 1T′-MoS2 nanoribbons. Our results suggest that these nanoribbons could serve as promising candidates for future topological field-effect transistor (FET) technologies. Using first-principles density functional theory (DFT) in conjunction with maximally localized Wannier functions and non-equilibrium Green's function (NEGF) formalism, we analyze the evolution of electronic, topological, and transport properties under a perpendicular electric field. At zero field, 1T′-MoS2 exhibits a nontrivial Z2 invariant and robust edge states characteristic of a quantum spin Hall insulator. Increasing the electric field drives a transition from a topological insulator to a trivial insulator, accompanied by the suppression of conducting edge states. For nanoribbons, the applied field induces inversion-symmetry breaking, opening an energy gap and modulating edge-dominated transport channels. Transmittance spectra reveal quantized conductance steps, consistent with the presence of spin-polarized edge modes, while carrier density mapping confirms their strong localization at ribbon edges. These results establish 1T′-MoS2 nanoribbons as promising candidates for topological FETs, where electrically tunable on/off switching can be harnessed for low-power, dissipationless nanoelectronics devices.

Abstract In this paper, we demonstrate the phase transition of 1T ′ -WTe 2 armchair and zigzag edge nanoribbons under the application of an out-of-plane electric field normal to the monolayer plane. Density functional theory, Heyd–Scuseria–Ernzerhof and maximally localized Wannier functions are utilized to determine the properties of the material, and the transport calculations are performed using non-equilibrium green’s function method and tight-binding model. By using these calculations, we have observed that 1T ′ -WTe 2 changes its phase from topological insulator to trivial insulator after the application of a critical electric field, E = 0.216 V Å − 1 . Moreover, the edge transport phenomena, which are observed in both nanoribbons of 1T ′ -WTe 2 , can contribute to the development of low-energy, dissipationless devices, particularly for designing a topological field-effect transistor.

In this paper, we demonstrate the phase transition of 1T-WTearmchair and zigzag edge nanoribbons under the application of an out-of-plane electric field normal to the monolayer plane. Density functional theory, Heyd-Scuseria-Ernzerhof and maximally localized Wannier functions are utilized to determine the properties of the material, and the transport calculations are performed using non-equilibrium green's function method and tight-binding model. By using these calculations, we have observed that 1T-WTechanges its phase from topological insulator to trivial insulator after the application of a critical electric field,= 0.216. Moreover, the edge transport phenomena, which are observed in both nanoribbons of 1T-WTe, can contribute to the development of low-energy, dissipationless devices, particularly for designing a topological field-effect transistor.

We investigate quantum spin hall properties of 1T'-WTe2 with spin orbit coupling. The up spin and down spin orbital bands are degenerate. After applying an electric field, the up spin and down spin bands split from each other. We observe the phase transition from topological insulator to trivial insulator due to electric field, which is very important for the use of the material as channel material in field effect transistors. All calculations are conducted using density functional theory and maximally localized wannier functions.

In this paper, we have investigated the transport of topological edge states in 2D Zigzag edge Tungsten Ditelluride Nanoribbon (ZTDNR).We have found that zigzag edge nanoribbon (NR) of Tungsten Ditelluride develops topological edge states in the presence of intrinsic spin orbit interaction (SOC). We have used three band tight binding model for the electrons of d z 2 , d xy , and d x 2 - y 2 orbitals with SOC for calculating band structure of NR and Non Equilibrium Greens Function (NEGF) formalism for transport in the NR. We have investigated transport in a pristine device, transport in the presence of a finite potential barrier, transport with constriction within the device and transport with edge imperfections.

The quantum transport properties of electrons in 2D hexagonal lattice Molybdenum di-selenide (MoSe 2 ) armchair and zigzag nanoribbons are investigated using Non-Equilibrium Green's function (NEGF) formalism and 11- band Tight-Binding model. The armchair nanoribbon shows presence of bandgap while the zigzag nanoribbon shows edge states in a single edge with Dirac like E-K diagram.

Electron transport properties in 2D hexagonal lattice topological insulators (TI) under photon interaction are investigated using Non Equilibrium Green's Function (NEGF) formalism and Haldane model. Back scattering less transport of electrons in valence band and conduction band (after photo-excitation) is observed. The result of this research can be utilized for design of nano-scale optoelectronic coherent electron devices.