Suppressing Twin Domains in Molecular Beam Epitaxy Grown Bi₂Te₃ Topological Insulator Thin Films

Abstract

The structural perfection of the topological insulator (TI) Bi2Te3 is a key issue for its employment in future device applications. State of the art TIs, featuring exotic electronic properties, predominantly suffer from structural defects such as twin domains. A suppression of such domains in molecular beam epitaxy-grown Bi2Te3 thin films on Si(111) substrates—measured by X-ray diffraction pole figure scans—is presented in this paper. A numerical analysis of van der Waals potentials was performed, revealing the nucleation collinear with the Si(311) reflections of the Si(111) substrate to be energetically preferred.