Out-of-plane transport of 1T-TaS2/graphene-based van der Waals heterostructures

Abstract

Due to their anisotropy, layered materials are excellent candidates for studying the interplay between the in-plane and out-of-plane entanglement in strongly correlated systems. A relevant example is provided by 1T-TaS2, which exhibits a multifaceted electronic and magnetic scenario due to the existence of several charge density wave (CDW) configurations. It includes quantum hidden phases, superconductivity and exotic quantum spin liquid (QSL) states, which are highly dependent on the out-of-plane stacking of the CDW. In this system, the interlayer stacking of the CDW is crucial for the interpretation of the underlying electronic and magnetic phase diagram. Here, thin-layers of 1T-TaS2 are integrated in vertical van der Waals heterostructures based on few-layer graphene (FLG) contacts and their electrical transport properties are measured. Different activation energies in the conductance and a gap at the Fermi level are clearly observed. Our experimental findings are supported by fully self-consistent DFT+U calculations, which evidence the presence of an energy gap in the few-layer limit, not necessarily coming from the formation of out-of-plane spin-paired bilayers at low temperatures, as previously proposed for the bulk. These results highlight dimensionality as a key effect for understanding the properties of 1T-TaS2 and opens the door to the possible experimental realization of low-dimensional QSLs.

Main Text (5 figures)

References in corpus (13)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Gate-tunable Phase Transitions in 1T-TaS${}_2$
• Quantum Hall effect and Landau level crossing of Dirac fermions in trilayer graphene
• Self-consistent Hubbard parameters from density-functional perturbation theory in the ultrasoft and projector-augmented wave formulations
• Band insulator to Mott insulator transition in 1T-TaS${}_2$
• Gapless excitations in the ground state of 1T-TaS${}_2$
• The low-temperature highly correlated quantum phase in the charge-density-wave 1T-TaS_2 compound
• Possible strain induced Mott gap collapse in 1T-TaS${}_2$
• Identification of the Mott insulating CDW state in 1T-TaS${}_2$
• Direct Observation of Mono-, Bi-, and Tri-layer Charge Density Waves in 1T-TaS_2 by Transmission Electron Microscopy without a Substrate
• Gate- and Light-Tunable Negative Differential Resistance with High Peak Current Density in 1T-TaS${}_2$/2H-MoS${}_2$ T-Junction
• Zoology of domain walls in quasi-2D correlated charge density wave of 1T-TaS2
• van der Waals heterostructures based on atomically-thin superconductors

Cited by in corpus (13)

• Multistep magnetization switching in orthogonally twisted ferromagnetic monolayers
• Probing the spin dimensionality in single-layer CrSBr van der Waals heterostructures by magneto-transport measurements
• Chemical design and magnetic ordering in thin layers of 2D MOFs
• Programmable Magnetic Hysteresis in Orthogonally-Twisted Two-Dimensional CrSBr Magnets via Stacking Engineering
• Spin-orbit and exchange proximity couplings in graphene/1T-TaS${}_2$ heterostructure triggered by a charge density wave
• Probing quantum spin liquids with a quantum twisting microscope
• Charge density wave surface reconstruction in a van der Waals layered material
• Probing Short-Range Correlations in the van der Waals Magnet CrSBr by Small-Angle Neutron Scattering
• Probing enhanced superconductivity in van der Waals polytypes of V${}_x$TaS${}_2$
• Insights on the coupling between vibronically active molecular vibrations and lattice phonons in molecular nanomagnets
• Comment on "Identification of the Mott Insulating Charge Density Wave State in $1T$-TaS${}_2$"
• Strongly Enhanced Charge-Density Waves and Correlated Insulating State in Atomically Thin 1$T$-TaS${}_2$
• Strain Switching in van der Waals Heterostructures triggered by a Spin-Crossover Metal Organic Framework