Molecular beam epitaxial growth of a three-dimensional topological Dirac semimetal Na3Bi

Abstract

We report a molecular beam epitaxial growth of Na3Bi single-crystal thin films on two different substrates-epitaxial bilayer graphene terminated 6H-SiC(0001) and Si(111). Using reflection high-energy electron diffraction, we found that the lattice orientation of the grown Na3Bi thin film was rotated by 30 degrees respect to the surface lattice orientations of these two substrates. An in-situ angle-resolved photoemission spectroscopy clearly revealed the 3-dimensional Dirac-cone band structure in such thin films. Our approach of growing Na3Bi thin film provides a potential route for further studying its intriguing electronic properties and for fabricating it into practical devices in future. (C) 2014 AIP Publishing LLC