On the quantum spin Hall gap of monolayer 1T'-WTe2

Abstract

Quantum spin Hall (QSH) materials are two-dimensional systems exhibiting insulating bulk and helical edge states simultaneously. A QSH insulator processes topologically non-trivial edge states protected by time-reversal symmetry, so that electrons can propagate unscattered. Realization of such topological phases enables promising applications in spintronics, dissipationless transport and quantum computations. Presently, realization of such QSH-based devices are limited to complicated heterostructures. Monolayer 1T'-WTe2 was predicted to be semimetallic QSH materials, though with a negative band gap. The quasi-particle spectrum obtained using hybrid functional approach shows directly that the quantum spin Hall gap is positive for monolayer 1T'-WTe2. Optical measurement shows a systematic increase in the interband relaxation time with decreasing number of layers, whereas transport measurement reveals Schottcky barrier in ultrathin samples, which is absent for thicker samples. These three independent pieces of evidence indicate that monolayer 1T'-WTe2 is likely a truly 2-dimensional quantum spin Hall insulator.

arXiv comment21 pages, 6 figures; Has been published online by Advanced Materials (2016)

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Cited by in corpus (65)

• Realization of Quantum Spin Hall State in Monolayer 1T'-WTe2
• Observation of the Quantum Spin Hall Effect up to 100 Kelvin in a Monolayer Crystal
• Observation of the nonlinear Hall effect under time reversal symmetric conditions
• Electrically Tunable Low Density Superconductivity in a Monolayer Topological Insulator
• Electrically switchable Berry curvature dipole in the monolayer topological insulator WTe2
• Band signatures for strong nonlinear Hall effect in bilayer WTe${}_2$
• Observation of topological states residing at step edges of WTe2
• Evidence for a Monolayer Excitonic Insulator
• Raman signatures of inversion symmetry breaking and structural phase transition in type-II Weyl semimetal MoTe2
• Direct Visualization of 2D Topological Insulator in Single-layer 1T'-WTe2
• Evidence for equilibrium excitons and exciton condensation in monolayer WTe2
• Origins of the structural phase transitions in MoTe${}_2$ and WTe${}_2$
• Theoretical Prediction of Two-Dimensional Functionalized MXene Nitrides as Topological Insulators
• Inversion-protected higher order topological superconductivity in monolayer WTe${}_2$
• Strain Tunable Semimetal-Topological-Insulator Transition in Monolayer 1T'-WTe2
• Abundance of ${\mathbb{Z}}_2$ topological order in exfoliable two-dimensional insulators
• Landau Quantization and Highly Mobile Fermions in an Insulator
• Observation of Coulomb gap in the quantum spin Hall candidate single-layer 1T'-WTe${}_2$
• Atomically Thin Quantum Spin Hall Insulators
• Machine learning driven synthesis of few-layered WTe2
• 2024 roadmap on 2D topological insulators
• Qsymm: Algorithmic symmetry finding and symmetric Hamiltonian generation
• Quantum anomalous Hall effect in stable 1T-YN${}_2$ monolayer with a large nontrivial band gap and high Chern number
• Anisotropic longitudinal optical conductivities of tilted Dirac bands in 1T${}^{\prime }$-MoS${}_2$
• Intrinsic Phonon Bands in High-Quality Monolayer T' Molybdenum Ditelluride
• The influence of lattice termination on the edge states of the quantum spin Hall insulator monolayer $1T^{\prime }$-WTe${}_2$
• Custodial glide symmetry of quantum spin Hall edge modes in WTe${}_2$ monolayer
• Stanene: A Good Platform for Topological Insulator and Topological Superconductor
• Tailoring the Phase Transition and Electron-Phonon Coupling in 1T'-MoTe2 by Charge Doping: A Raman Study
• Experimental Progress on Layered Topological Semimetals
• Laser-beam patterned topological insulating states on thin semiconducting MoS2
• Electric field effects on the band gap and edge states of monolayer 1T'-WTe2
• Effect of aging-induced disorder on the quantum transport properties of atomically thin WTe${}_2$
• Thickness dependent electronic structure in WTe${}_2$ thin films
• Tunable Low-Loss Hyperbolic Plasmon Polaritons in a T${}_d$-WTe${}_2$ Single Layer
• Absence of equilibrium edge currents in theoretical models of topological insulators
• Enhanced superconductivity in bilayer PtTe${}_2$ by alkali-metal intercalations
• Multi-Band Superconductivity in Strongly Hybridized 1T'-WTe${}_2$/NbSe${}_2$ Heterostructures
• Observation of highly anisotropic bulk dispersion and spin-polarized topological surface states in CoTe2
• Evidence of Electron-Hole Imbalance in WTe2 from High-Resolution Angle-Resolved Photoemission Spectroscopy
• Barkhausen effect in the first order structural phase transition in type-II Weyl semimetal MoTe2
• A gate-tunable quantum phase transition in a topological excitonic insulator
• Fast electrically switchable large gap quantum spin Hall states in MGe${}_2$Z${}_4$
• Raman spectrum of 1T'-WTe2 under tensile strain: A first-principles prediction
• Electronic structure of molecular beam epitaxy grown 1T${}^{\prime }$-MoTe${}_2$ film and strain effect
• Theory of Glide Symmetry Protected Helical Edge States in WTe${}_2$ Monolayer
• Multi-frequency Shubnikov-de Haas oscillations in topological semimetal Pt${}_2$HgSe${}_3$
• Dynamical spin-to-charge conversion on the edge of quantum spin Hall insulator
• Higher-order topological superconductivity in monolayer WTe${}_2$ from repulsive interactions
• Low-energy effective theory and anomalous Hall effect in monolayer ${\mathrm{WTe}}_2$
• Emergent $Z_2$ Topological Invariant and Robust Helical Edge States in Two-Dimensional Topological Metals
• Engineering chiral edge states in 2D topological insulator/ferromagnetic insulator heterostructures
• Metal-to-superconductor Transition Induced by Lithium Adsorption on Monolayer 1$T$-Nb${}_2$C
• Thermal robustness of the quantum spin Hall phase in monolayer WTe${}_2$
• Quantum oscillation study of the large magnetoresistance in Mo substituted WTe${}_2$ single crystals
• Strain-dependent one-dimensional confinement channels in twisted bilayer 1T${}^{\prime }$-WTe${}_2$
• Theory of Nonlocal Transport from Nonlinear Valley Responses
• Electronic properties of the steps in bilayer Td-WTe2
• Unusual temperature dependence of the band structure associated with local atomic distortion in monolayer 1T'-WTe2
• Persistent spin texture preserved by local symmetry in graphene/WTe${}_2$ heterostructure
• Probing the topological protection of edge states in multilayer tungsten ditelluride with the superconducting proximity effect
• Excitonic and magnetic phases in doped WTe${}_2$ monolayers: a Hartree-Fock approach
• Intrinsic nonlinear valley Nernst effect
• Stabilization of sliding ferroelectricity through exciton condensation
• Room-Temperature Noncolinear Ferroelectricity in van der Waals WO${}_2$Cl${}_2$ with a Wide Bandgap