Band gap anomaly and topological properties in lead chalcogenides

Abstract

Band gap anomaly is a well-known issue in lead chalcogenides PbX (X=S, Se, Te, Po). Combining ab initio calculations and tight-binding (TB) method, we have studied the band evolution in PbX, and found that the band gap anomaly in PbTe is mainly related to the high onsite energy of Te 5s orbital and the large s-p hopping originated from the irregular extended distribution of Te 5s electrons. Furthermore, our calculations show that PbPo is an indirect band gap (6.5 meV) semiconductor with band inversion at L point, which clearly indicates that PbPo is a topological crystalline insulator (TCI). The calculated mirror Chern number and surface states double confirm this conclusion.

7 pages and 4 figures

References in corpus (5)

• Topological Crystalline Insulators
• Large-Gap Two-Dimensional Topological Insulator in Oxygen Functionalized MXene
• Exploration and prediction of topological electronic materials based on first-principles calculations
• Quantum Spin Hall Effect in 2D Transition Metal Dichalcogenide Haeckelites
• Quantum Anomalous Hall Effect in Magnetic Insulator Heterostructure

Cited by in corpus (3)

• Emphanitic anharmonicity in PbSe at high temperature and the anomalous electronic properties in the PbQ (Q=S, Se, Te) system
• Topological Electronic States in HfRuP Family Superconductors
• Discovery of Ĉ${}_2$ rotation anomaly in topological crystalline insulator SrPb