Realization of AlSb in the double layer honeycomb structure: a robust new class of two-dimensional material

Abstract

Exploring new two-dimensional (2D) van der Waals (vdW) systems is at the forefront of materials physics. Here, through molecular beam epitaxy on graphene-covered SiC(0001), we report successful growth of AlSb in the double-layer honeycomb (DLHC) structure, a 2D vdW material which has no direct analogue to its 3D bulk and is predicted kinetically stable when freestanding. The structural morphology and electronic structure of the experimental 2D AlSb are characterized with spectroscopic imaging scanning tunneling microscopy and cross-sectional imaging scanning transmission electron microscopy, which compare well to the proposed DLHC structure. The 2D AlSb exhibits a bandgap of 0.93 eV versus the predicted 1.06 eV, which is substantially smaller than the 1.6 eV of bulk. We also attempt the less-stable InSb DLHC structure; however, it grows into bulk islands instead. The successful growth of a DLHC material here opens the door for the realization of a large family of novel 2D DLHC traditional semiconductors with unique excitonic, topological, and electronic properties.

arXiv comment21 pages, 6 figures

References in corpus (19)

• Van der Waals heterostructures
• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Epitaxial Growth of Two-Dimensional Stanene
• Direct observation of the transition from indirect to direct bandgap in atomically thin epitaxial MoSe2
• Large-gap quantum spin Hall insulators in tin films
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Bismuthene on a SiC Substrate: A Candidate for a New High-Temperature Quantum Spin Hall Paradigm
• Realization of Quantum Spin Hall State in Monolayer 1T'-WTe2
• Direct observation of high temperature superconductivity in one-unit-cell FeSe films
• Epitaxial growth of large-gap quantum spin Hall insulator on semiconductor surface
• Observation of topological states residing at step edges of WTe2
• Quantum-spin-Hall insulator with a large gap: single-layer 1T' WSe${}_2$
• Universal stability of two-dimensional traditional semiconductors
• A universal description of III-V/Si epitaxial growth processes
• Realizing intrinsic excitonic insulator by decoupling exciton binding energy from the minimum band gap
• Excitonic Instability and Electronic Property of Two-dimensional AlSb Limit
• Mott phase in a van der Waals transition-metal halide at single layer limit
• Possible phason-polaron effect on purely one dimensional charge order of Mo6Se6 nanowires

Cited by in corpus (4)

• Excitonic Instability and Electronic Property of Two-dimensional AlSb Limit
• Large spin splitting and piezoelectricity in a two-dimensional topological insulator Al${}_2$SbBi with double-layer honeycomb structure
• First-principles design of excitonic insulators: A review
• Stable phases of freestanding monolayer TiO${}_2$: The emergence of out-of-plane ferroelectricity