Distinctive momentum dependent charge-density-wave gap observed in CsV${}_3$Sb${}_5$ superconductor with topological Kagome lattice

Abstract

CsV${}_3$Sb${}_5$ is a newly discovered Kagome superconductor that attracts great interest due to its topological nontrivial band structure and the coexistence of superconductivity and charge-density-wave (CDW) with many exotic properties. Here, we report the detailed characterization of the CDW gap in high-quality CsV${}_3$Sb${}_5$ single crystals using high-resolution angle-resolved photoemission spectroscopy. We find that the CDW gap is strongly momentum dependent. While gapped around the $M$ point, the electronic states remain gapless around the $\Gamma$ point and along the $\Gamma$-$K$ direction. Such momentum dependence indicates that the CDW is driven by the scattering of electrons between neighboring $M$ points, where the band structure hosts multiple saddle points and the density of state diverges near the Fermi level. Our observations of the partially gapped Fermi surface and strongly momentum-dependent CDW gap not only provide a foundation for uncovering the mechanism of CDW in CsV${}_3$Sb${}_5$, but also shed light on the understanding of how the CDW coexists with superconductivity in this topological Kagome superconductor.

arXiv comment10 pages, 4 figures

References in corpus (7)

• Roton pair density wave and unconventional strong-coupling superconductivity in a topological kagome metal
• Charge density waves and electronic properties of superconducting kagome metals
• Double superconducting dome and triple enhancement of Tc in the kagome superconductor CsV3Sb5 under high pressure
• Concurrence of anomalous Hall effect and charge density wave in a superconducting topological kagome metal
• Pressure-induced Reemergence of Superconductivity in Topological Kagome Metal CsV3Sb5
• Origin of the Charge Density Wave in the Kagome Metal CsV${}_3$Sb${}_5$ as Revealed by Optical Spectroscopy
• Anisotropic proximity-induced superconductivity and edge supercurrent in Kagome metal, K1-xV3Sb5

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• Quantum states and intertwining phases in kagome materials
• Mechanism of exotic density-wave and beyond-Migdal unconventional superconductivity in kagome metal AV3Sb5 (A=K, Rb, Cs)
• Chern Fermi pocket, topological pair density wave, and charge-4e and charge-6e superconductivity in kagome superconductors
• Electron-phonon coupling in the charge density wave state of CsV${}_3$Sb${}_5$
• Possible star-of-David pattern charge density wave with additional modulation in the kagome superconductor CsV${}_3$Sb${}_5$
• Evidence of a hidden flux phase in the topological kagome metal CsV${}_3$Sb${}_5$
• A unique van Hove singularity in kagome superconductor CsV${}_{3-x}$Ta${}_x$Sb${}_5$ with enhanced superconductivity
• No observation of chiral flux current in the topological kagome metal CsV${}_3$Sb${}_5$
• Anomalous thermoelectric effects and quantum oscillations in the kagome metal CsV${}_3$Sb${}_5$
• Charge-loop current order and Z3 nematicity mediated by bond-order fluctuations in kagome metal AV3Sb5 (A=Cs,Rb,K)
• Role of Sb in the superconducting kagome metal CsV${}_3$Sb${}_5$ revealed by its anisotropic compression
• Three-dimensional energy gap and origin of charge-density wave in kagome superconductor KV3Sb5
• Carrier Injection and Manipulation of Charge-Density Wave in Kagome Superconductor CsV3Sb5
• Evolution of electronic structure in pristine and hole-doped kagome metal RbV${}_3$Sb${}_5$
• Dynamical Study of the Origin of the Charge Density Wave in $A$V${}_3$Sb${}_5$ ($A=$K, Rb, Cs) Compounds
• Spectroscopic Evidence for a Three-Dimensional Charge Density Wave in Kagome Superconductor CsV${}_3$Sb${}_5$
• Magneto-Seebeck effect and ambipolar Nernst effect in CsV${}_3$Sb${}_5$ superconductor
• Multidome superconductivity in charge density wave kagome metals
• Electronic properties of correlated kagomé metals AV${}_3$Sb${}_5$(A = K, Rb, Cs): A perspective
• Dirac Nodal Lines and Nodal Loops in a Topological Kagome Superconductor CsV${}_3$Sb${}_5$
• Pressure evolution of electron dynamics in the superconducting kagome metal CsV${}_3$Sb${}_5$
• Two-dimensional phase diagram of the charge density wave in doped CsV${}_3$Sb${}_5$