Electrostatically Induced Superconductivity at the Surface of WS${}_2$

Abstract

We investigate transport through ionic liquid gated field effect transistors (FETs) based on exfoliated crystals of semiconducting WS${}_2$. Upon electron accumulation, at surface densities close to -or just larger than- 10${}^{14}$ cm${}^{-2}$, transport exhibits metallic behavior, with the surface resistivity decreasing pronouncedly upon cooling. A detailed characterization as a function of temperature and magnetic field clearly shows the occurrence of a gate-induced superconducting transition below a critical temperature $T_c\approx 4$ K, a finding that represents the first demonstration of superconductivity in tungsten-based semiconducting transition metal dichalcogenides. We investigate the nature of superconductivity and find significant inhomogeneity, originating from the local detaching of the frozen ionic liquid from the WS${}_2$ surface. Despite the inhomogeneity, we find that in all cases where a fully developed zero resistance state is observed, different properties of the devices exhibit a behavior characteristic of a Berezinskii-Kosterlitz-Thouless transition, as it could be expected in view of the two-dimensional nature of the electrostatically accumulated electron system.

arXiv comment18 pages, 4 figures; Nano Letters (2015)

References in corpus (17)

• Atomically thin MoS2: A new direct-gap semiconductor
• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• Control of valley polarization in monolayer MoS2 by optical helicity
• Valley polarization in MoS2 monolayers by optical pumping
• MoS_2 as an ideal material for valleytronics: valley-selective circular dichroism and valley Hall effect
• The Valley Hall Effect in MoS2 Transistors
• Mobility engineering and metal-insulator transition in monolayer MoS2
• Electrically Tunable Excitonic Light Emitting Diodes based on Monolayer WSe2 p-n Junctions
• Optoelectronics with electrically tunable PN diodes in a monolayer dichalcogenide
• Optical Generation of Excitonic Valley Coherence in Monolayer WSe2
• Solar-energy conversion and light emission in an atomic monolayer p-n diode
• Electroluminescence in Single Layer MoS2
• Electrical Transport Properties of Single-Layer WS2
• Quantitative Determination of the Band-Gap of WS2 with Ambipolar Ionic Liquid-Gated Transistors
• Mono- and Bilayer WS2 Light-Emitting Transistors
• Broadening of the Beresinkii-Kosterlitz-Thouless superconducting transition by inhomogeneity and finite-size effects
• Scanning photocurrent microscopy reveals electron-hole asymmetry in ionic liquid-gated WS2 transistors

Cited by in corpus (50)

• Highly crystalline 2D superconductors
• Pressure-driven dome-shaped superconductivity and electronic structural evolution in tungsten ditelluride
• Gate-induced Superconductivity in atomically thin MoS2 crystals
• Metallic ground state in an ion-gated two-dimensional superconductor
• Topological superconductivity in monolayer transition metal dichalcogenides
• First-principles theory of field-effect doping in transition-metal dichalcogenides: Structural properties, electronic structure, Hall coefficient, and electrical conductivity
• Superconductivity in potassium-doped metallic polymorphs of MoS2
• A full superconducting dome of strong Ising protection in gated monolayer WS2
• Disorder engineering and conductivity dome in ReS2 with electrolyte gating
• Gate-Induced Interfacial Superconductivity in 1T-SnSe2
• Tunneling spectroscopy of gate-induced superconductivity in MoS${}_2$
• Superconductivity in Potassium-intercalated Td-WTe2
• Microscopic Origin of the Valley Hall Effect in Transition Metal Dichalcogenides Revealed by Wavelength Dependent Mapping
• Odd-parity superconductivity in bilayer transition metal dichalcogenides
• Enhanced electron-phonon interaction in multi-valley materials
• Gated Tuned Superconductivity and Phonon Softening in Mono- and Bilayer MoS${}_2$
• 2D superconductivity and vortex dynamics in 1T-MoS2
• Ionic Gate Spectroscopy of 2D Semiconductors
• Oxygen Electromigration and Energy Band Reconstruction Induced by Electrolyte Field Effect at Oxide Interfaces
• Control of bulk superconductivity in a BCS superconductor by surface charge doping via electrochemical gating
• Superconductivity in monolayer Ba${}_2$N electride: a first-principles study
• Proximity Eliashberg theory of electrostatic field-effect-doping in superconducting films
• A DMRG study: Pair-density wave in spin-valley locked systems
• Weak Localization in Electric-Double-Layer Gated Few-layer Graphene
• Unconventional superconductivity from magnetism in transition metal dichalcogenide
• Interplay of screening and superconductivity in low-dimensional materials
• Lithium-ion conducting glass ceramics for electrostatic gating
• Negative electronic compressibility and nanoscale inhomogeneity in ionic-liquid gated two-dimensional superconductors
• Metal-insulator transition in monolayer MoS${}_2$ via contactless chemical doping
• Zero point motion and direct/indirect bandgap crossover in layered transition-metal dichalcogenides
• Mapping multi-valley Lifshitz transitions induced by field-effect doping in strained MoS2 nanolayers
• Non-invasive control of excitons in two-dimensional materials
• Ionic gating in metallic superconductors: A brief review
• Anomalous screening of an electrostatic field at the surface of niobium nitride
• Full control of solid-state electrolytes for electrostatic gating
• Two-band superconductivity of bulk and surface states in Ag thin films on Nb
• The impact of valley profile on the mobility and Kerr rotation of transition metal dichalcogenides
• Identifying Topological Superconductivity in 2D Transition-Metal Dichalcogenides
• Photon drag of superconducting fluctuations in 2D systems
• Temperature effect on lattice and electronic structures of WTe${}_2$ from first-principles study
• Two-dimensional hole transport in ion-gated diamond surfaces: A brief review
• Superfluid response of an atomically thin, gate-tuned van der Waals superconductor
• Anomalous metallic phase in molybdenum disulphide induced via gate-driven organic ion intercalation
• Strong band-filling-dependence of the scattering lifetime in gated MoS2 nanolayers induced by the opening of intervalley scattering channels
• Breakdown of the Hebel-Slichter effect in superconducting graphene due to the emergence of Yu-Shiba-Rusinov states at magnetic resonant scatterers
• Demonstration of Electric Double Layer Gating under High Pressure by the Development of Field-Effect Diamond Anvil Cell
• Spin relaxation, Josephson effect and Yu-Shiba-Rusinov states in superconducting bilayer graphene
• Ionic-liquid-gating setup for stable measurements and reduced electronic inhomogeneity at low temperatures
• Observation of surface superconductivity in bulk polycrystalline MoS2 induced by electric double-layer doping
• Enhanced Backgate Tunability on Interfacial Carrier Concentration in Ionic Liquid-Gated MoS2 Devices