Epitaxial growth of Bi, Sb, and Sn

Abstract

Graphene analogs composed of Bi, Sb, and Sn, respectively, are predicted to be great candidates to realize the quantum spin Hall effect at high temperatures and have attracted intensive research interest in recent years. However, their structural and electronic properties are greatly affected by substrates. Here, we epitaxially grow Bi, Sb, and Sn overlayers on various substrates. We observed the formation of Au–Bi alloy on Au(111) substrates, while α-Bi was formed on the TaIrTe4, TiSe2and Cr2Ge2Te6 substrates. Large-scale thin films of α-Bi, α-Sb and β-Sn can be prepared on the TiSe2 substrates due to the high quality of the substrates with very few defects. The lattice of the Sb films is slightly compressed on the TiSe2 substrates, due to the interfacial interaction. α-Sn transitions to β-Sn on the TiSe2 substrates with increasing Sn coverages. Our work is very helpful for tuning the structural and electronic properties of epitaxial Bi, Sb, and Sn films via proper substrates.