Thickness dependence of work function, ionization energy, and electron affinity of Mo and W dichalcogenides from DFT and GW calculations

Abstract

Transition-metal dichalcogenides (TMDs) are promising for two-dimensional (2D) semiconducting devices and novel phenomena. For 2D applications, their work function, ionization energy, and electron affinity are required as a function of thickness, but research on this is yet to cover the full family of compounds. Here, we present the work function, ionization energy, and electron affinity of few-layer and bulk MX2 (M = Mo, W and X = S, Se, Te) in 2H phase obtained accurately by the density functional theory and GW calculations. For each compound, we consider one-, two-, three-, four-layer, and bulk geometry. In GW calculations, accurate results are obtained by nonuniform q sampling for two-dimensional geometry. From band energies including the GW self-energy correction, we estimate the work function, band gap, ionization energy, and electron affinity as functions of the number of layers. We compare our results with available theoretical and experimental reports, and we discuss types of band alignments in in-plane and out-of-plane junctions of these few-layer and bulk TMDs.

10 pages, 5 figures, 7 tables

References in corpus (30)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Atomically thin MoS2: A new direct-gap semiconductor
• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• MoS_2 as an ideal material for valleytronics: valley-selective circular dichroism and valley Hall effect
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
• The Valley Hall Effect in MoS2 Transistors
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Direct observation of the transition from indirect to direct bandgap in atomically thin epitaxial MoSe2
• Three-band tight-binding model for monolayers of group-VIB transition metal dichalcogenides
• BerkeleyGW: A Massively Parallel Computer Package for the Calculation of the Quasiparticle and Optical Properties of Materials and Nanostructures
• Quasiparticle Self-Consistent GW Theory
• Magnetic Control of Valley Pseudospin in Monolayer WSe2
• Renormalization of Molecular Electronic Levels at Metal-Molecule Interfaces
• Valley Zeeman Effect in Elementary Optical Excitations of a Monolayer WSe2
• Band alignment of two-dimensional transition metal dichalcogenides: application in tunnel field effect transistors
• Breaking of valley degeneracy by magnetic field in monolayer MoSe2
• Concepts of Ferrovalley Material and Anomalous Valley Hall Effect
• Valley-selective optical Stark effect in monolayer WS2
• Valley Splitting and Polarization by the Zeeman Effect in Monolayer MoSe2
• Electrical control of the valley Hall effect in bilayer MoS2 transistors
• Macroscopic polarization and band offsets at nitride heterojunctions
• Screening and Many-Body Effects in Two-Dimensional Crystals: Monolayer MoS${}_2$
• Ultrafast Generation of Pseudo-magnetic Field for Valley Excitons in WSe2 Monolayers
• Coulomb-hole summations and energies for GW calculations with limited number of empty orbitals: a modified static remainder approach
• Probing the Role of Interlayer Coupling and Coulomb Interactions on Electronic Structure in Few-Layer MoSe2 Nanostructures
• Quasiparticle band-edge energy and band offsets of monolayer of molybdenum and tungsten chalcogenide
• Non-uniform sampling schemes of the Brillouin zone for many-electron perturbation-theory calculations in reduced dimensionality
• Substrate screening effects on the quasiparticle band gap and defect charge transition levels in MoS${}_2$
• Microscopic Origin of the Valley Hall Effect in Transition Metal Dichalcogenides Revealed by Wavelength Dependent Mapping
• Origin of layer dependence in band structures of two-dimensional materials

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