Recent Advances in Tin: From Two-Dimensional Quantum Spin Hall Insulator to Bulk Dirac Semimetal

Abstract

An atomic layer of tin in a buckled honeycomb lattice, termed stanene, is a promising large-gap two-dimensional topological insulator for realizing room-temperature quantum-spin-Hall effect and therefore has drawn tremendous interest in recent years. Because the electronic structures of Sn allotropes are sensitive to lattice strain, e.g. the semimetallic αphase of Sn can transform into a three-dimensional topological Dirac semimetal under compressive strain, recent experimental advances have demonstrated that stanene layers on different substrates can also host various electronic properties relating to in-plane strain, interfacial charge transfer, layer thickness, and so on. Thus, comprehensive understanding of the growth mechanism at the atomic scale is highly desirable for precise control of such tunable properties. Herein, the fundamental properties of stanene and α-Sn films, recent achievements in epitaxial growth, challenges in high-quality synthesis, and possible applications of stanene are discussed.

Superconducting Long-Range Proximity Effect through the Atomically Flat Interface of a Bi2Te3 Topological Insulator

“…[25][26][27][28] In this respect, the interface between superconductors (S) and a topological insulator (TI) is expected to induce by proximity peculiar properties such as unconventional superconductivity. 20,25 Topologically protected surface states [29][30][31][32][33][34][35][36][37] are not only attractive from the fundamental point of view, such as the realization of Majorana modes, [38][39][40] but also for spintronics applications, in the view of their robustness and the forbidden backscattering. [41][42][43] The couple Pb/Bi 2 Te 3 is a good candidate for such a study.…”

Epitaxial Growth of Main Group Monoelemental 2D Materials

“…Theoretically, monolayer Sn adopting a buckled honeycomb structure is a TI with a band gap of 100 meV. [ 136 ] The epitaxial growth of Sn thin films has been investigated for decades. [ 137 ] One representative substrate is InSb(111), which is terminated with either In or Sb atoms, termed A or B face, respectively.…”

How Oxygen Absorption Affects the Al2O3‐Encapsulated Blue Phosphorene–Au Alloy

“…[1] Among them, the honeycomb lattices made of elements of the column IVA (below carbon) have attracted much interest because of their potential applications in the electronics industry, such as silicon and germanium, or for recent outcomes related to topological physics, such as tin. [2][3][4] Xene-like silicene, germanene, and stanene show properties akin to graphene and the increasing mass of the X element from carbon to tin enables the opening of a bandgap due to spin-orbit coupling effects, e.g., up to 0.3 eV for stanene on Cu(111), [5] compatible with technological applications, especially in the electronics field, where graphene suffers from intrinsic limitations. [1] Another route to reach out the same goal, i.e., bandgap opening, is looking at neighbor elements of the IVA column.…”