Band Alignment of 2D Semiconductors for Designing Heterostructures with Momentum Space Matching

TL;DR

This paper systematically analyzes the band alignments of various 2D semiconductors to identify momentum-matched heterojunctions, creating a comprehensive guide for designing novel atomic heterostructures with specific electronic properties.

Contribution

It provides a detailed first-principles study of band alignments across multiple 2D materials, establishing a periodic table of heterojunction types based on momentum space matching.

Findings

Nearly half of the studied materials have band edges at the zone center.

903 heterojunction combinations characterized for their type.

Identification of potential atomic heterostructures with momentum-matched band edges.

Abstract

We present a comprehensive study of the band alignments of two-dimensional (2D) semiconducting materials and highlight the possibilities of forming momentum-matched type I, II and III heterojunctions; an enticing possibility being atomic heterostructures where the constituent monolayers have band edges at the zone center. Our study, which includes the Group IV and III-V compound monolayer materials, Group V elemental monolayer materials, transition metal dichalcogenides (TMD) and transition metal trichalcogenides (TMT) reveals that almost half of these materials have conduction and/or valence band edges residing at the zone center. Using first-principles density functional calculations, we present the type of the heterojunction for 903 different possible combination of these 2D materials which establishes a periodic table of heterojunctions.