Universal stability of two-dimensional traditional semiconductors

TL;DR

This paper demonstrates that a wide range of traditional semiconductors become stable in a two-dimensional double layer honeycomb structure, revealing new 2D materials with potential topological properties.

Contribution

It introduces a large class of stable 2D semiconductors derived from traditional bulk materials, expanding the landscape of 2D materials with novel electronic features.

Findings

26 semiconductors stabilize in DLHC form in 2D limit

Traditional semiconductors can exhibit topological properties in 2D form

Ultra-thin limit favors DLHC structure over bulk forms

Abstract

Interest in two dimensional materials has exploded in recent years. Not only are they studied due to their novel electronic properties, such as the emergent Dirac Fermion in graphene, but also as a new paradigm in which stacking layers of distinct two dimensional materials may enable different functionality or devices. Here, through first-principles theory, we reveal a large new class of two dimensional materials which are derived from traditional III-V, II-VI, and I-VII semiconductors. It is found that in the ultra-thin limit all of the traditional binary semi-conductors studied (a series of 26 semiconductors) stabilize in a two dimensional double layer honeycomb (DLHC) structure, as opposed to the wurtzite or zinc-blende structures associated with three dimensional bulk. Not only does this greatly increase the landscape of two-dimensional materials, but it is shown that in the double layer honeycomb form, even ordinary semiconductors, such as GaAs, can exhibit exotic topological properties.