The enabling electronic motif for topological insulation in ABO3 perovskites and its structural stability
arXiv:1611.06839
Abstract
Stable oxide topological insulators (TIs) that could bring together the traditional oxide functionalities with the dissipationless surface states of TIs have been sought for years but none was found. Yet, heavier chalcogenides (selenides, tellurides) were readily found to be TIs. We clarify here the basic contradiction between TI-ness and stability which is maximal for oxides, and trace the basic design principles necessary to identify the window of opportunity of stable TIs. We first identify the electronic motif that can achieve topological band inversion ("topological gene") in ABO3 as being a lone-pair electron-rich B atom (e.g. Te, I, Bi) at the octahedral site. We then illustrate that poorly screened oxide systems with large inversion energies can undergo energy-lowering atomic distortions that remove the band inversion. We identify the coexistence windows of TI functionality and structure stability for different pressures and find that the common cubic ABO3 structures have inversion energies lying outside this coexistence window at zero pressure but could be moved into the coexistence window at moderate pressures. Our study demonstrates the interplay between topological band inversion and structural stability and traces the basic principles needed to design stable oxide topological insulators at ambient pressures.
References in corpus (13)
- Topological Order and the Quantum Spin Hall Effect
- Topological Insulators with Inversion Symmetry
- Topological Crystalline Insulators in the SnTe Material Class
- Tensor-Entanglement-Filtering Renormalization Approach and Symmetry Protected Topological Order
- Time Reversal Polarization and a Z_2 Adiabatic Spin Pump
- An equivalent expression of Z2 Topological Invariant for band insulators using Non-Abelian Berry's connection
- Interface engineering of quantum Hall effects in digital transition metal oxide heterostructures
- Topological surface state in the Kondo Insulator Samarium Hexaboride
- A large energy-gap oxide topological insulator based on the superconductor BaBiO3
- In-Plane Orbital Texture Switch at the Dirac Point in the Topological Insulator Bi2Se3
- Plutonium hexaboride is a correlated topological insulator
- Lone Pair Effect, Structural Distortions and Potential for Superconductivity in Tl Perovskites
- Topological nature and the multiple Dirac cones hidden in Bismuth high-Tc superconductors