Emergent quantum Hall effects below $50$ mT in a two-dimensional topological insulator

Abstract

The realization of the quantum spin Hall effect in HgTe quantum wells has led to the development of topological materials which, in combination with magnetism and superconductivity, are predicted to host chiral Majorana fermions. However, the large magnetization ($\sim$ a few tesla) in conventional quantum anomalous Hall system, makes it challenging to induce superconductivity. Here, we report two different emergent quantum Hall effects in HgTe quantum wells dilutely alloyed with Mn. Firstly, a novel quantum Hall state emerges from the quantum spin Hall state at an exceptionally low magnetic field of $\sim 50$ mT. Secondly, tuning towards the bulk $p$-regime, we resolve multiple quantum Hall plateaus at fields as low as $20-30$ mT, where transport is dominated by a van Hove singularity in the valence band. These emergent quantum Hall phenomena rely critically on the topological band structure of HgTe and their occurrence at very low fields make them an ideal candidate for interfacing with superconductors to realize chiral Majorana fermions.

References in corpus (18)

• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Topological orders and Edge excitations in FQH states
• Quantum Anomalous Hall Effect in Hg${}_{1-y}$Mn${}_y$Te Quantum Wells
• Chiral Topological Superconductor From the Quantum Hall State
• Quantum Hall Effect from the Topological Surface States of Strained Bulk HgTe
• Band structure of semimagnetic Hg1-yMnyTe quantum wells
• Inelastic electron backscattering in a generic helical edge channel
• Resistance of helical edges formed in a semiconductor heterostructure
• Interacting topological edge channels
• Ballistic quantum spin Hall state and enhanced edge backscattering in strong magnetic fields
• Magnetic properties of HgTe quantum wells
• Strain Engineering of the Band Gap of HgTe Quantum Wells using Superlattice Virtual Substrates
• Survival of the quantum anomalous Hall effect in orbital magnetic fields as a consequence of the parity anomaly
• Spin-orbit splitting of valence and conduction bands in HgTe quantum wells near the Dirac point

Cited by in corpus (23)

• Electric control of a canted-antiferromagnetic Chern insulator
• Quantum Hall phase in graphene engineered by interfacial charge coupling
• Momentum-resolved spin splitting in Mn-doped trivial CdTe and topological HgTe semiconductors
• Effects of charge dopants in quantum spin Hall materials
• Topological states in superlattices of HgTe-class materials for engineering three-dimensional flat bands
• Quantitative theory of backscattering in topological HgTe and (Hg,Mn)Te quantum wells: acceptor states, Kondo effect, precessional dephasing, and bound magnetic polaron
• Massive and topological surface states in tensile strained HgTe
• Engineering topological phases in triple HgTe/CdTe quantum wells
• Breakdown of helical edge state topologically protected conductance in time-reversal-breaking excitonic insulators
• Relativistic and nonrelativistic Landau levels for the noncommutative quantum Hall effect with anomalous magnetic moment in a conical Gödel-type spacetime
• Theory of Glide Symmetry Protected Helical Edge States in WTe${}_2$ Monolayer
• Electron-hole scattering limited transport of Dirac fermions in a topological insulator
• Engineering axion insulator phase in superlattices with inversion symmetry breaking
• kdotpy: $\mathbf{k}\cdot \mathbf{p}$ theory on a lattice for simulating semiconductor band structures
• Parity symmetry as the origin of 'spin' in the quantum spin Hall effect
• Finite field transport response of a dilute magnetic topological insulator based Josephson junction
• Spectral asymmetry induces a re-entrant quantum Hall effect in a topological insulator
• Topological band inversion in HgTe(001): surface and bulk signatures from photoemission
• CdTe and HgTe doped with V, Cr, and Mn -- prospects for the quantum anomalous Hall effect
• Tight-binding theory of spin-spin interactions, Curie temperatures, and quantum Hall effects in topological (Hg,Cr)Te in comparison to non-topological (Zn,Cr)Te, and (Ga,Mn)N
• HgTe quantum wells for QHE metrology under soft cryomagnetic conditions: permanent magnets and liquid ${}^{4}He$ temperatures
• Role of magnetic doping in topological HgTe and application of the Gram-Schmidt method for computing impurity states in quantum wells
• Counterpropagating topological and quantum Hall edge channels