Evidence of orbit-selective electronic kagome lattice with planar flat-band in correlated paramagnetic YCr6Ge6

Abstract

Electronic properties of kagome lattice have drawn great attention recently. In associate with flat-band induced by destructive interference and Dirac cone-type dispersion, abundant exotic phenomena have been theoretically discussed. The material realization of electronic kagome lattice is a crucial step towards comprehending kagome physics and achieving novel quantum phases. Here, combining angle-resolved photoemission spectroscopy, transport measurements and first-principle calculations, we expose a planar flat-band in paramagnetic YCr6Ge6 as a typical signature of electronic kagome lattice. We unearth that the planar flat-band arises from the d_(z^2 ) electrons with intra-kagome-plane hopping forbidden by destructive interference. On the other hand, the destructive interference and flatness of the d_(x^2-y^2 ) and d_xy bands are decomposed possibly due to additional in-plane hopping terms, but the Dirac cone-type dispersion is reserved near chemical potential. We explicitly unveil that orbital character plays an essential role to realize electronic kagome lattice in bulk materials with transition metal kagome layers. Paramagnetic YCr6Ge6 provides an opportunity to comprehend intrinsic properties of electronic kagome lattice as well as its interplays with spin orbit coupling and electronic correlation of Cr-3d electrons, and be free from complications induced by strong local moment of ions in kagome planes.

References in corpus (30)

• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Quantum Spin Liquid States
• Giant anomalous Hall effect in a ferromagnetic Kagome-lattice semimetal
• High temperature fractional quantum Hall states
• Fractionalized excitations in the spin liquid state of a kagomé lattice antiferromagnet
• Fractional quantum Hall states at zero magnetic field
• Quantum Spin Liquids
• Massive Dirac fermions in a ferromagnetic kagome metal
• Nearly-flat bands with nontrivial topology
• Large anomalous Hall effect driven by non-vanishing Berry curvature in non-collinear antiferromagnetic Mn3Ge
• Dirac fermions and flat bands in the ideal kagome metal FeSn
• Large intrinsic anomalous Hall effect in half-metallic ferromagnet Co3Sn2S2 with magnetic Weyl fermions
• Evidence for Magnetic Weyl Fermions in a Correlated Metal
• Flat bands and Wigner crystallization in the honeycomb optical lattice
• Discovery of a quantum limit Chern magnet TbMn6Sn6
• Negative flat band magnetism in a spin-orbit coupled correlated kagome magnet
• Topological flat bands in frustrated kagome lattice CoSn
• Giant and anisotropic many-body spin-orbit tunability in a strongly correlated kagome magnet
• Fractional Quantum Hall Effect of Hard-Core Bosons in Topological Flat Bands
• Intrinsic Quantum Anomalous Hall Effect in the Kagome Lattice Cs2LiMn3F12
• Orbital-selective Dirac fermions and extremely flat bands in frustrated kagome-lattice metal CoSn
• Anomalous Hall effect of ferromagnetic Fe3Sn2 single crystal with geometrically frustrated kagome lattice
• Charge-order-assisted topological surface states and flat bands in the kagome superconductor CsV${}_3$Sb${}_5$
• Fantastic flat bands and where to find them: The CoSn-type compounds
• Realizing Kagome Band Structure in Two-Dimensional Kagome Surface States of $R{V}_{6}S{n}_6$ ($R$=Gd,Ho)
• Creating Weyl nodes and controlling their energy by magnetization rotation
• Proposed realization of itinerant ferromagnetism in optical lattices
• Fermion-boson many-body interplay in a frustrated kagome paramagnet
• YCr6Ge6 as a Candidate Compound for a Kagome Metal

Cited by in corpus (9)

• Quantum states and intertwining phases in kagome materials
• Emergence of flat bands and ferromagnetic fluctuations via orbital-selective electron correlations in Mn-based kagome metal
• Observation of flat and weakly dispersing bands in a van der Waals semiconductor Nb3Br8 with breathing kagome lattice
• Optical anisotropy of the kagome magnet FeSn: Dominant role of excitations between kagome and Sn layers
• Electronic Correlation Effects on Stabilizing a Perfect Kagome Lattice and Ferromagnetic Fluctuation in LaRu${}_3$Si${}_2$
• MPd5 kagome superconductors studied by density functional calculations
• Coexisting Kagome and Heavy Fermion Flat Bands in YbCr${}_6$Ge${}_6$
• Crystal structure, properties and pressure-induced insulator-metal transition in layered kagome chalcogenides
• Singular flat bands in three dimensions: Landau level spreading, quantum geometry, and Weyl reconstruction