Observation of a multitude of correlated states at the surface of bulk 1T-TaSe${}_2$ crystals

Abstract

The interplay between electron-electron interactions and structural ordering can yield exceptionally rich correlated electronic phases. We have used scanning tunneling microscopy to investigate bulk 1T-TaSe2 and have uncovered surprisingly diverse correlated surface states thereof. These surface states exhibit the same in-plane charge density wave ordering but dramatically different electronic ground states ranging from insulating to metallic. The insulating variety of surface state shows signatures of a decoupled surface Mott layer. The metallic surface states, on the other hand, exhibit zero-bias peaks of varying strength that suggest Kondo phases arising from coupling between the Mott surface layer and the metallic bulk of 1T-TaSe2. The surface of bulk 1T-TaSe2 thus constitutes a rare realization of the periodic Anderson model covering a wide parameter regime, thereby providing a model system for accessing different correlated phenomena in the same crystal. Our results highlight the central role played by strong correlations in this material family.

References in corpus (23)

• Scanning Tunneling Spectroscopy of Graphene on Graphite
• Observation of Landau levels of Dirac fermions in graphite
• Is 1T-TaS${}_2$ a 40 year old quantum spin liquid?
• Orbital textures and charge density waves in transition metal dichalcogenides
• A metallic mosaic phase and the origin of Mott insulating state in 1T-TaS2
• Nanoscale manipulation of the Mott insulating state coupled to charge order in 1T-TaS2
• Visualizing Exotic Orbital Texture in the Single-Layer Mott Insulator 1T-TaSe2
• Three Dimensional Metallic and Two Dimensional Insulating Behavior in Tantalum Dichalcogenides
• Imaging spinon density modulations in a 2D quantum spin liquid
• Mottness versus unit-cell doubling as the driver of the insulating state in 1T-TaS2
• Disrupted orbital order and the pseudo-gap in layered 1T-TaS${}_2$
• Spinon Fermi surface in a cluster Mott insulator model on a triangular lattice and possible application to 1T-TaS${}_2$
• Spectroscopic signatures of a bandwidth-controlled Mott transition at the surface of 1T-TaSe${}_2$
• Monolayer 1T-NbSe2 as a 2D correlated magnetic insulator
• Kondo proximity effect: How does a metal penetrate into a Mott insulator?
• Orbital density wave order and electronic correlation driven insulating 1T-TaS2 monolayer
• Evidence for a spinon Kondo effect in cobalt atoms on single-layer 1T-TaSe${}_2$
• Periodic Anderson model with correlated conduction electrons
• Coupling between Charge, Lattice, Orbital, and Spin in a Charge Density Wave of 1$T$-TaS${}_2$
• Pair Density Wave in the Doped $t$-$J$ Model with Ring Exchange on a Triangular Lattice
• Reconcile the Bulk Metallic and Surface Insulating state in 1T-TaSe${}_2$
• Competition of Spinon Fermi Surface and Heavy Fermi Liquids states from the Periodic Anderson to the Hubbard model
• Doublon-like excitations and their phononic coupling in a Mott charge-density-wave system

Cited by in corpus (1)

• Nature of metallic and insulating domains in the CDW system 1T-TaSe2