Electron delocalization in a 2D Mott insulator
arXiv:2405.09877 · doi:10.1038/s41467-024-54747-4
Abstract
The prominent role of electron-electron interactions in two-dimensional (2D) materials versus three-dimensional (3D) ones is at the origin of the great variety of fermionic correlated states reported in the literature. In this respect, artificial van der Waals heterostructures comprising single layers of highly correlated insulators allow one to explore the effect of the subtle interlayer interaction in the way electrons correlate. In this work, we study the temperature dependence of the electronic properties of a van der Waals heterostructure composed of a single-layer Mott insulator lying on a metallic substrate by performing quasi-particle interference (QPI) maps. We show the emergence of a Fermi contour in the 2D Mott insulator at temperatures below 11K, which we attribute to the delocalization of the Mott electrons associated with the formation of a quantum coherent Kondo lattice. This Kondo lattice introduces a new periodicity in the system, so that the resulting Fermi surface encompasses both the substrate conduction electrons and the now delocalized correlated electrons from the 2D Mott insulator. Density Functional Theory calculations allow us to pinpoint the scattering vectors responsible for the experimentally observed quasi-particle interference maps, thus providing a complete picture of the delocalization of highly correlated electrons in a 2D Mott insulator.
15 pages, 4 figures
References in corpus (16)
- Van der Waals heterostructures
- 2D materials and van der Waals heterostructures
- Evidence of Ising pairing in superconducting NbSe atomic layers
- Van der Waals heterostructures for spintronics and opto-spintronics
- Imaging the Fano Lattice to 'Hidden Order' Transition in URu2Si2
- Structure and Control of Charge Density Waves in Two-Dimensional 1T-TaS2
- Nanoscale manipulation of the Mott insulating state coupled to charge order in 1T-TaS2
- Visualizing heavy fermions emerging in a quantum critical Kondo lattice
- Quasiparticle interference of the Fermi arcs and surface-bulk connectivity of a Weyl semimetal
- Imaging spinon density modulations in a 2D quantum spin liquid
- Visualization of Topological Boundary Modes Manifesting Topological Nodal-Point Superconductivity
- Remnant Fermi surface in the presence of an underlying instability in layered 1T-TaS_2
- Heterogeneous Ta-dichalcogenide bilayer: heavy fermions or doped Mott physics?
- Realization of metallic state in 1T-TaS2 with persisting long-range order of charge density wave
- Probing the phase transition to a coherent 2D Kondo lattice
- Ab-initio Theory of Fourier-transformed Quasiparticle Interference Maps and Application to the Topological Insulator BiTe