Termination-dependent surface properties in the giant-Rashba semiconductorsBiTeX(X=Cl, Br, I)

Abstract

The non-centrosymmetric semiconductors BiTeX (X = Cl, Br, I) show large Rashba-type spinorbit splittings in their electronic structure making them candidate materials for spin-based electronics. However, BiTeI(0001) single crystal surfaces usually consist of stacking-fault-induced domains of Te and I terminations implying a spatially inhomogeneous electronic structure. Here we combine scanning tunneling microscopy (STM), photoelectron spectroscopy (ARPES, XPS) and density functional theory (DFT) calculations to systematically investigate the structural and electronic properties of BiTeX (0001) surfaces. For X = Cl, Br we observe macroscopic single-terminated surfaces. We discuss chemical characteristics among the three materials in terms of bonding character, surface electronic structure, and surface morphology.

Pressure-induced topological phase transition in the polar semiconductor BiTeBr

“…Furthermore, scanning tunneling microscopy revealed the distribution of submicron-scale domains composed of p-and n-type semiconducting domains with opposite stacking sequences in BiTeI [15]. Since BiTeBr has no such domains [16], it is not necessary to consider its effect on evaluating transport properties under high pressure.…”

Optical, electronic, and elastic properties of some A5B6C7ferroelectrics (A=Sb, Bi; B=S, Se; C=I, Br, Cl): First principle calculation

“…The large Rashba-type spin-orbit-coupling (SOC) in the bulk and surface electronic structure of these compounds has recently attracted great interest [6][7][8][9][10]. The Rashba effect can be utilized in important spintronics applications, such as the spin-based transistor [11].…”

“…Akrapet et al [15] investigated the optical properties and Raman spectra of BiTeBr and BiTeCl single crystal using chemical vapor transport and topotactic methods. Fiedler et al [9] investigated the surface structural and electronic properties of the semiconductors BiTeX (X D Cl, Br, I) using the various techniques. Moreschiniet et al [16] investigated the surface states using the QUANTUM-ESPRESSO package.…”

Vibrational properties of layered BiTeCl single crystal

“…Such as BiTeI has Te and I termination domains in the same cleaved surface, and their boundaries can form in‐plane p–n junctions . For BiTeCl, Te and Cl atoms are in separate layers forming vertical p–n junctions . Even at Г point, BiTeCl and BiTeI have different electronic structures besides band gaps, which might also induce different interband transitions.…”

“…As one member of bismuth tellurohalides BiTeX (X═I, Cl, and Br), BiTeCl with its unique merits for 2D device applications still remains less explored. BiTeCl cleaved surfaces can be clean n‐type Te terminated or p‐type Cl terminated with high contamination, forming novel vertical p–n junctions . For samples of nanometer thickness, gigapascal‐level effective pressure can be formed along the polar axis direction, which is a different feature from nonpolar graphene and transitional metal dichalcogenides (TMDCs).…”