High-order van Hove singularities and nematic instability in the kagome superconductor CsTi${}_3$Bi${}_5$

Abstract

ATi${}_3$Bi${}_5$ (A = Cs or Rb) are emerging topological kagome metals that exhibit superconductivity and nematicity without intertwining translational symmetry-breaking charge orders. In this work, we explore the fermiology of their titanium kagome electrons and identify a set of sublattice-pure, high-order van Hove singularities (VHSs) that can suppress charge ordering and enhance electronic correlations and superconductivity. Our calculations of charge susceptibility for kagome bands with both normal and high-order VHSs emphasize the role of these VHSs in driving electronic nematicity in CsTi${}_3$Bi${}_5$. Additionally, we compute the phonon spectrum and electron-phonon interactions for CsTi${}_3$Bi${}_5$ under pristine, doped, and kagome-exposed surface conditions, revealing its robustness against structural instabilities while enhancing the superconducting transition temperature. Our work positions ATi${}_3$Bi${}_5$ as a key platform for investigating superconductivity and electronic nematicity without translational symmetry-breaking states in kagome metals.

References in corpus (38)

• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Topological Insulators with Inversion Symmetry
• CsV${}_3$Sb${}_5$: a ${\mathbb{Z}}_2$ topological kagome metal with a superconducting ground state
• Roton pair density wave and unconventional strong-coupling superconductivity in a topological kagome metal
• Discovery of a quantum limit Chern magnet TbMn6Sn6
• Charge density waves and electronic properties of superconducting kagome metals
• Superconductivity in the ${\mathbb{Z}}_2$ kagome metal KV${}_3$Sb${}_5$
• Concurrence of anomalous Hall effect and charge density wave in a superconducting topological kagome metal
• Three-dimensional charge density wave and robust zero-bias conductance peak inside the superconducting vortex core of a kagome superconductor CsV${}_3$Sb${}_5$
• Topological Weyl semimetals in the chiral antiferromagnetic materials Mn3Ge and Mn3Sn
• Observation of Unconventional Charge Density Wave without Acoustic Phonon Anomaly in Kagome Superconductors AV3Sb5 (A=Rb,Cs)
• Analysis of Charge Order in the Kagome Metal $A$V${}_3$Sb${}_5$ ($A=$K,Rb,Cs)
• Nature of unconventional pairing in the kagome superconductors AV${}_3$Sb${}_5$
• Rich Nature of Van Hove Singularities in Kagome Superconductor CsV${}_3$Sb${}_5$
• Complex charge density waves at Van Hove singularity on hexagonal lattices: Haldane-model phase diagram and potential realization in kagome metals ${\text{AV}}_3{\text{Sb}}_5$
• Charge density wave in kagome lattice intermetallic ScV6Sn6
• Anomalous transport due to Weyl fermions in the chiral antiferromagnets Mn${}_3$$X$, $X$ = Sn, Ge
• Quantum states and intertwining phases in kagome materials
• Chern Fermi pocket, topological pair density wave, and charge-4e and charge-6e superconductivity in kagome superconductors
• Chiral excitonic order from twofold van Hove singularities in kagome metals
• Softening of a flat phonon mode in the kagome ScV${}_6$Sn${}_6$
• Competing charge-density wave instabilities in the kagome metal ScV${}_6$Sn${}_6$
• Abundant lattice instability in kagome metal ScV${}_6$Sn${}_6$
• Observation of Flat Band, Dirac Nodal Lines and Topological Surface States in Kagome Superconductor CsTi${}_3$Bi${}_5$
• Electronic nematicity without charge density waves in titanium-based kagome metal
• A new class of bilayer kagome lattice compounds with Dirac nodal lines and pressure-induced superconductivity
• Non-trivial band topology and orbital-selective electronic nematicity in a new titanium-based kagome superconductor
• Superconductivity and orbital-selective nematic order in a new titanium-based kagome metal CsTi3Bi5
• The kagomé metals RbTi${}_3$Bi${}_5$ and CsTi${}_3$Bi${}_5$
• Tunable van Hove singularity without structural instability in Kagome metal CsTi${}_3$Bi${}_5$
• Large kagome family candidates with topological superconductivity and charge density waves
• Visualizing nematic transition and nanoscale suppression of superconductivity in Fe(Te,Se)
• Dynamics and Resilience of the Charge Density Wave in a bilayer kagome metal
• Superconducting, topological and transport properties of kagome metals CsTi${}_3$Bi${}_5$ and RbTi${}_3$Bi${}_5$
• Van-Hove annihilation and nematic instability on a Kagome lattice
• Electrical and thermal transport properties of kagome metals $A$Ti${}_3$Bi${}_5$ ($A$ = Rb, Cs)
• Enhanced nematicity emerging from higher-order van Hove singularities
• Competing Lattice Instability and Magnetism on the Surface of Kagome Metals

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