Abstract

Momentum-matched type II van der Waals heterostructures (vdWHs) have been designed by assembling layered two-dimensional semiconductors (2DSs) with special band-structure combinations – that is, the valence band edge at the Γ point for one 2DS and the conduction band edge at the Γ point for the other. Based on density-functional theory calculations, the paper probes interfacial effects including different quasichemical-bonding interactions for valence and conduction bands, interface dipole, and their synergy on band-edge evolution in energy and valley, using monolayer InSe and bilayer WS₂ as a typical vdWH example. It then proposes a practical screening method for robust momentum-matched type II vdWHs.

Abstract

Momentum-matched type II van der Waals heterostructures (vdWHs) have been designed by assembling layered two-dimensional semiconductors (2DSs) with special band-structure combinations – that is, the valence band edge at the Γ point for one 2DS and the conduction band edge at the Γ point for the other. Based on density-functional theory calculations, the paper probes interfacial effects including different quasichemical-bonding interactions for valence and conduction bands, interface dipole, and their synergy on band-edge evolution in energy and valley, using monolayer InSe and bilayer WS₂ as a typical vdWH example. It then proposes a practical screening method for robust momentum-matched type II vdWHs.

Abstract

Momentum-matched type II van der Waals heterostructures (vdWHs) have been designed by assembling layered two-dimensional semiconductors (2DSs) with special band-structure combinations – that is, the valence band edge at the Γ point for one 2DS and the conduction band edge at the Γ point for the other. Based on density-functional theory calculations, the paper probes interfacial effects including different quasichemical-bonding interactions for valence and conduction bands, interface dipole, and their synergy on band-edge evolution in energy and valley, using monolayer InSe and bilayer WS₂ as a typical vdWH example. It then proposes a practical screening method for robust momentum-matched type II vdWHs.

Abstract

Momentum-matched type II van der Waals heterostructures (vdWHs) have been designed by assembling layered two-dimensional semiconductors (2DSs) with special band-structure combinations – that is, the valence band edge at the Γ point for one 2DS and the conduction band edge at the Γ point for the other. Based on density-functional theory calculations, the paper probes interfacial effects including different quasichemical-bonding interactions for valence and conduction bands, interface dipole, and their synergy on band-edge evolution in energy and valley, using monolayer InSe and bilayer WS₂ as a typical vdWH example. It then proposes a practical screening method for robust momentum-matched type II vdWHs.