Intrinsic large gap quantum anomalous Hall insulators in La$X$ ($X$=Br, Cl, I)

Abstract

We report a theoretical prediction of a new class of bulk and intrinsic quantum Anomalous Hall (QAH) insulators La$X$ ($X$=Br, Cl, and I) via relativistic first-principle calculations. We find that these systems are innate long-ranged ferromagnets which, with the help of intrinsic spin-orbit coupling, become QAH insulators. A low-energy multiband tight binding model is developed to understand the origin of the QAH effect. Finally integer Chern number is obtained via Berry phase computation for each two-dimensional plane. These materials have the added benefit of a sizable band gap of as large as $\sim$ 25 meV, with the flexibility of enhancing it to above 75 meV via strain engineering. The synthesis of La$X$ materials will provide the impurity-free single crystals and thin-film QAH insulators for versatile experiments and functionalities.

16 pages (including appendix and supp. mat)

References in corpus (14)

• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Valley-Polarized Metals and Quantum Anomalous Hall Effect in Silicene
• High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator
• Quantum Anomalous Hall Effect in Hg${}_{1-y}$Mn${}_y$Te Quantum Wells
• Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects
• Quantum Anomalous Hall Effect in Graphene Proximity Coupled to an Antiferromagnetic Insulator
• Line of Dirac Nodes in Hyper-Honeycomb Lattices
• Quantum Anomalous Hall State in Bilayer Graphene
• Tunable Line Node Semimetals
• Chern insulators from heavy atoms on magnetic substrates
• Topological phases in layered pyrochlore oxide thin films along the [111] direction
• Chern insulator at a magnetic rocksalt interface
• Quantum anomalous Hall phase in (001) double-perovskite monolayers via intersite spin-orbit coupling

Cited by in corpus (5)

• Multiple-Fold Fermions and Topological Fermi Arcs Induced Catalytic Enhancement in Nanoporous Electride C12A7
• Quantum Anomalous Hall Effect in Magnetic Doped Topological Insulators and Ferromagnetic Spin-Gapless Semiconductors -- A Perspective Review
• Chern insulators without band inversion in MoS2 monolayers with 3d adatoms
• Discovering two-dimensional magnetic topological insulators by machine learning
• In-plane magnetization orientation driven topological phase transition in OsCl${}_3$ monolayer