Epitaxial growth of antiferromagnetic MnBi2Te4/CdTe heterostructures on GaAs(001) using molecular beam epitaxy: structure and electronic properties

Abstract

MnBi₂Te₄ is one of the most recent materials that integrates the class of topological quantum materials exhibiting topological insulating properties and magnetic ordering, thus providing the opportunity to investigate particular topological quantum states and design novel spintronic devices. The samples were grown on GaAs(100) substrates using molecular beam epitaxy with Bi₂Te₃, Te and Mn as sources. The growth was characterized through X-ray diffraction, atomic force microscopy and transmission electron microscopy. Topological insulator properties were probed through scanning tunneling microscopy and scanning tunneling spectroscopy, while antiferromagnetic order was investigated via magnetotransport measurements. Furthermore, we propose a high-quality CdTe thin film as a cap layer to protect topological surface states, thus opening the possibility of integrating topological quantum materials with group II–VI semiconductors via van der Waals epitaxy.