Functionalized Bismuth Films: Giant Gap Quantum Spin Hall and Valley-Polarized Quantum Anomalous Hall States

Abstract

The search for new large band gap quantum spin Hall (QSH) and quantum anomalous Hall (QAH) insulators is critical for their realistic applications at room temperature. Here we predict, based on first principles calculations, that the band gap of QSH and QAH states can be as large as 1.01 eV and 0.35 eV in an H-decorated Bi(111) film. The origin of this giant band gap lies both in the large spin-orbit interaction of Bi and the H-mediated exceptional electronic and structural properties. Moreover, we find that the QAH state also possesses the properties of quantum valley Hall state, thus intrinsically realising the so-called valley-polarized QAH effect. We further investigate the realization of large gap QSH and QAH states in an H-decorated Bi(\={1}10) film and X-decorated (X=F, Cl, Br, and I) Bi(111) films.

submitted to Physical Reveiw Letters on 25th of September 2014

References in corpus (19)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Control of graphene's properties by reversible hydrogenation
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Graphane: a two-dimensional hydrocarbon
• The Valley Hall Effect in MoS2 Transistors
• Quantum Spin Hall Effect in Inverted Type II Semiconductors
• Quantum Anomalous Hall Effect in Hg${}_{1-y}$Mn${}_y$Te Quantum Wells
• Quantum Spin Hall Effect and Enhanced Magnetic Response by Spin-Orbit Coupling
• Quantum Anomalous Hall Effect in Graphene Proximity Coupled to an Antiferromagnetic Insulator
• One-dimensional Topological Edge States of Bismuth Bilayers
• Prediction of Near-Room-Temperature Quantum Anomalous Hall Effect on Honeycomb Materials
• Epitaxial growth of large-gap quantum spin Hall insulator on semiconductor surface
• Direct Evidence for the Dirac-Cone Topological Surface States in Ternary Chalcogenide TlBiSe2
• Edge and Interfacial States in a 2D Topological Insulator:Bi(111) Bilayer on Bi${}_2$Te${}_2$Se
• Creation of Helical Dirac Fermions by Interfacing Two Gapped Systems of Ordinary Fermions

Cited by in corpus (5)

• Bulk quantum Hall effect of spin-valley-coupled Dirac fermions in a polar antiferromagnet BaMnSb${}_2$
• Robust Dual Topological Character with Spin-Valley Polarization in a Monolayer of the Dirac Semimetal Na${}_3$Bi
• Topological Crystalline Insulator and Quantum Anomalous Hall States in IV-VI based Monolayers and their Quantum Wells
• Topological Phase Transition Coupled with Spin-Valley Physics in Ferroelectric Oxide Heterostructures
• Quantized Thermal Hall Conductance and the Topological Phase Diagram of a Superconducting Bismuth Bilayer