Alternating superconducting and charge density wave monolayers within bulk 6R-TaS2

Abstract

Van der Waals (vdW) heterostructures continue to attract intense interest as a route of designing materials with novel properties that cannot be found in naturally occurring materials. Unfortunately, this approach is currently limited to only a few layers that can be stacked on top of each other. Here we report a bulk material consisting of superconducting monolayers interlayered with monolayers displaying charge density waves (CDW). This bulk vdW heterostructure is created by phase transition of 1T-TaS2 to 6R at 800 °C in an inert atmosphere. Electron microscopy analysis directly shows the presence of alternating 1T and 1H monolayers within the resulting bulk 6R phase. Its superconducting transition (Tc) is found at 2.6 K, exceeding the Tc of the bulk 2H phase of TaS2. The superconducting temperature can be further increased to 3.6 K by exfoliating 6R-TaS2 and then restacking its layers. Using first-principles calculations, we argue that the coexistence of superconductivity and CDW within 6R-TaS2 stems from amalgamation of the properties of adjacent 1H and 1T monolayers, where the former dominates the superconducting state and the latter the CDW behavior.

References in corpus (9)

• 2D materials and van der Waals heterostructures
• Ultrafast Charge Transfer in Atomically Thin MoS2/WS2 Heterostructures
• Vertical Field Effect Transistor based on Graphene-WS2 Heterostructures for flexible and transparent electronics
• Light-emitting diodes by bandstructure engineering in van der Waals heterostructures
• Highly crystalline 2D superconductors
• Franckeite: a naturally occurring van der Waals heterostructure
• Atomic Lattice Disorder in Charge Density Wave Phases of Exfoliated Dichalcogenides (1T-TaS2)
• Light-Matter Coupling in Scalable Van der Waals Superlattices
• Anisotropic superconductivity in topological crystalline metal Pb${}_{1/3}$TaS${}_2$ with multiple Dirac fermions

Cited by in corpus (7)

• Pressure induced nonmonotonic evolution of superconductivity in 6R-TaS2 with a natural bulk van der Waals heterostructure
• Nematic Ising superconductivity with hidden magnetism in few-layer 6R-TaS2
• Tuning Superconductivity and Charge Density Wave Order in 2H-TaSe2 by Modulating the Van Hove Singularity
• Ising superconductivity: a first-principles perspective
• A revisit of superconductivity in 4$H_b$-TaS${}_{2-2x}$Se${}_{2x}$ single crystals
• Interlayer charge transfer induced by electronic instabilities in the natural van der Waals hetrostructure 4H${}_b$-TaS${}_2$
• Emergent quantum phenomena in two-dimensional 1T-TaS2