Kagome materials $A$V${}_3$Sb${}_5$ ($A$=K,Rb,Cs): pairing symmetry and pressure-tuning studies

Abstract

The vanadium-based kagome metals $A$V${}_3$Sb${}_5$ ($A$ = K, Rb, and Cs) host a superconducting ground state that coexists with an unconventional charge density wave (CDW). The CDW state exhibits experimental signatures of chirality, electronic nematicity, and time-reversal-symmetry-breaking, raising the questions whether the superconductivity (SC) in $A$V${}_3$Sb${}_5$ may also be unconventional, how SC interplays with CDW, and how the two orders evolve upon tuning. This article reviews studies of the superconducting pairing symmetry, and the tuning of SC and CDW in the $A$V${}_3$Sb${}_5$ compounds. Various experimental techniques consistently find that CsV${}_3$Sb${}_5$ exhibits nodeless SC, which remains robust regardless whether the CDW is present. Under hydrostatic pressure, SC in $A$V${}_3$Sb${}_5$ becomes enhanced as the CDW is gradually suppressed, revealing a competition between the two orders. In CsV${}_3$Sb${}_5$, a new CDW state emerges under pressure that competes more strongly with SC relative to the CDW at ambient pressure, and results in two superconducting domes that coexist with CDW. After the CDW in $A$V${}_3$Sb${}_5$ is fully suppressed with hydrostatic pressure, a further increase in pressure leads to a nonmonotonic evolution of the superconducting transition temperature driven by lattice modulations. Thickness is shown to be a powerful tuning parameter in $A$V${}_3$Sb${}_5$ thin flakes, revealing the evolution of CDW and SC upon dimensional reduction, and can be combined with hydrostatic pressure to shed light on the interplay between SC and CDW. Based on results reviewed in this article, we discuss outstanding issues to be addressed in the $A$V${}_3$Sb${}_5$ systems.

References in corpus (91)

• CsV${}_3$Sb${}_5$: a ${\mathbb{Z}}_2$ topological kagome metal with a superconducting ground state
• Discovery of unconventional chiral charge order in kagome superconductor KV3Sb5
• Roton pair density wave and unconventional strong-coupling superconductivity in a topological kagome metal
• Topological kagome magnets and superconductors
• Time-reversal symmetry-breaking charge order in a kagome superconductor
• Hidden Magnetism and Quantum Criticality in the Heavy Fermion Superconductor CeRhIn5
• Superconductivity in the ${\mathbb{Z}}_2$ kagome metal KV${}_3$Sb${}_5$
• 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
• Three-dimensional charge density wave and robust zero-bias conductance peak inside the superconducting vortex core of a kagome superconductor CsV${}_3$Sb${}_5$
• Superconductivity and normal-state properties of kagome metal RbV3Sb5 single crystals
• Magnetic Penetration Depth in Unconventional Superconductors
• Unusual competition of superconductivity and charge-density-wave state in a compressed topological kagome metal
• Chiral flux phase in the Kagome superconductor AV${}_3$Sb${}_5$
• 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${}_5$
• Electronic Nature of Charge Density Wave and Electron-Phonon Coupling in Kagome Superconductor KV${}_3$Sb${}_5$
• Fermi surface mapping and the nature of charge density wave order in the kagome superconductor CsV${}_3$Sb${}_5$
• Kagome superconductors AV${}_3$Sb${}_5$ (A=K, Rb, Cs)
• Complex charge density waves at Van Hove singularity on hexagonal lattices: Haldane-model phase diagram and potential realization in kagome metals ${\text{AV}}_3{\text{Sb}}_5$
• Multiband superconductivity with sign-preserving order parameter in kagome superconductor CsV3Sb5
• Twofold symmetry of $c$-axis resistivity in topological kagome superconductor CsV${}_3$Sb${}_5$ with in-plane rotating magnetic field
• Three-state nematicity and magneto-optical Kerr effect in the charge density waves in kagome superconductors
• Electronic nature of chiral charge order in the kagome superconductor CsV3Sb5
• Pressure-induced Reemergence of Superconductivity in Topological Kagome Metal CsV3Sb5
• Intrinsic nature of chiral charge order in the kagome superconductor RbV3Sb5
• Iron pnictides as a new setting for quantum criticality
• s-wave superconductivity in kagome metal CsV${}_3$Sb${}_5$ revealed by ${}^{121/123}$Sb NQR and ${}^{51}$V NMR measurements
• Interplay between charge order and superconductivity in the kagome metal KV${}_3$Sb${}_5$
• AV${}_3$Sb${}_5$ Kagome Superconductors: Progress and Future Directions
• Tunable nodal kagome superconductivity in charge ordered RbV3Sb5
• Nodeless superconductivity in the kagome metal CsV${}_3$Sb${}_5$
• Highly-robust reentrant superconductivity in CsV3Sb5 under pressure
• Multiple Energy Scales and Anisotropic Energy Gap in the Charge-Density-Wave Phase of Kagome Superconductor CsV3Sb5
• Emergence of new van Hove singularities in the charge density wave state of a topological kagome metal RbV3Sb5
• Charge-order-assisted topological surface states and flat bands in the kagome superconductor CsV${}_3$Sb${}_5$
• Fermi level tuning and double-dome superconductivity in the kagome metals CsV${}_3$Sb${}_{5-x}$Sn${}_x$
• Universal self-field critical current for thin-film superconductors
• Nodeless electron pairing in CsV${}_3$Sb${}_5$-derived kagome superconductors
• Charge order breaks time-reversal symmetry in CsV${}_3$Sb${}_5$
• Charge-density-wave-induced bands renormalization and energy gaps in a kagome superconductor RbV3Sb5
• Competition of superconductivity and charge density wave in selective oxidized CsV3Sb5 thin flakes
• Microscopic evidence for anisotropic multigap superconductivity in the CsV${}_3$Sb${}_5$ kagome superconductor
• Charge order landscape and competition with superconductivity in kagome metals
• Possible star-of-David pattern charge density wave with additional modulation in the kagome superconductor CsV${}_3$Sb${}_5$
• Charge-Density-Wave-Induced Peak-Dip-Hump Structure and the Multiband Superconductivity in a Kagome Superconductor CsV${}_3$Sb${}_5$
• Ambient Pressure Structural Quantum Critical Point in the Phase Diagram of (Ca${}_x$Sr${}_{1-x}$)${}_3$Rh${}_4$Sn${}_{13}$
• Competition between charge-density-wave and superconductivity in the kagome metal RbV3Sb5
• Temperature-driven reorganization of electronic order in CsV${}_3$Sb${}_5$
• Revealing the competition between charge-density wave and superconductivity in CsV${}_3$Sb${}_5$ through uniaxial strain
• Evidence of a hidden flux phase in the topological kagome metal CsV${}_3$Sb${}_5$
• Double-dome superconductivity under pressure in the V-based Kagome metals AV3Sb5 (A = Rb and K)
• Coexistence of Tri-Hexagonal and Star-of-David Pattern in the Charge Density Wave of the Kagome Superconductor AV${}_3$Sb${}_5$
• Bulk evidence of anisotropic $s$-wave pairing with no sign change in the kagome superconductor CsV${}_3$Sb${}_5$
• Spatial symmetry constraint of charge-ordered kagome superconductor CsV${}_3$Sb${}_5$
• Conjoined Charge Density Waves in the Kagome Superconductor CsV3Sb5
• Coexistence of Multiple Stacking Charge Density Waves in Kagome Superconductor ${\mathrm{CsV}}_3{\mathrm{Sb}}_5$
• Tuning the competition between superconductivity and charge order in kagome superconductor Cs(V1-xNbx)3Sb5
• Anomalous thermoelectric effects and quantum oscillations in the kagome metal CsV${}_3$Sb${}_5$
• Multiple quantum phase transitions and superconductivity in Ce-based heavy fermions
• Tuning the van Hove singularities in AV${}_3$Sb${}_5$ (A = K, Rb, Cs) via pressure and doping
• Revealing the immediate formation of two-fold rotation symmetry in charge-density-wave state of Kagome superconductor CsV${}_3$Sb${}_5$ by optical polarization rotation measurement
• Structural evolution of the kagome superconductors $A$V${}_3$Sb${}_5$ ($A$ = K, Rb, and Cs) through charge density wave order
• Competing superconductivity and charge-density wave in Kagome metal CsV3Sb5: evidence from their evolutions with sample thickness
• Nodeless superconductivity in kagome metal CsV${}_3$Sb${}_5$ with and without time reversal symmetry breaking
• Electronic nematicity without charge density waves in titanium-based kagome metal
• Pressure-induced dimensional crossover in a kagome superconductor
• Role of Sb in the superconducting kagome metal CsV${}_3$Sb${}_5$ revealed by its anisotropic compression
• Anomalous thermal Hall effect and anomalous Nernst effect of CsV${}_3$Sb${}_5$
• Strain-sensitive superconductivity in kagome metals KV${}_3$Sb${}_5$ and CsV${}_3$Sb${}_5$ probed by point-contact spectroscopy
• First-principles study on the double-dome superconductivities in kagome material CsV${}_3$Sb${}_5$ under pressure
• Microscopic nature of the charge-density wave in kagome superconductor RbV${}_3$Sb${}_5$
• Commensurate-to-incommensurate transition of charge-density-wave order and a possible quantum critical point in pressurized kagome metal CsV${}_3$Sb${}_5$
• Van Hove tuning of AV3Sb5 kagome metals under pressure and strain
• Muon-spin relaxation study of the layered kagome superconductor CsV${}_3$Sb${}_5$
• Tuning charge-density wave order and superconductivity in the kagome metals KV${}_3$Sb${}_{5-x}$Sn${}_x$ and RbV${}_3$Sb${}_{5-x}$Sn${}_x$
• Multidome superconductivity in charge density wave kagome metals
• Electronic properties of correlated kagomé metals AV${}_3$Sb${}_5$(A = K, Rb, Cs): A perspective
• Monolayer Kagome Metals AV${}_3$Sb${}_5$
• Evolution of charge density wave order and superconductivity under pressure in LaPt${}_2$Si${}_2$
• Superconducting, topological and transport properties of kagome metals CsTi${}_3$Bi${}_5$ and RbTi${}_3$Bi${}_5$
• Superconductivity modulated by structural phase transitions in pressurized vanadium-based kagome metals
• Evolution of superconductivity and charge order in pressurized RbV${}_3$Sb${}_5$
• Charge density wave and superconductivity in the kagome metal CsV${}_3$Sb${}_5$ around a pressure-induced quantum critical point
• Emergent superconducting fluctuations in a compressed kagome superconductor
• Electronic Correlations and Evolution of the Charge-Density Wave in the Kagome Metals $A$V${}_3$Sb${}_5$ ($A$ = K, Rb, Cs)
• Effect of nonhydrostatic pressure on the superconducting kagome metal CsV${}_3$Sb${}_5$
• Electrical and thermal transport properties of kagome metals AV${}_3$Sb${}_5$ (A=K, Rb, Cs)
• Evidence for an odd-parity nematic phase above the charge density wave transition in kagome metal CsV${}_3$Sb${}_5$
• Distinct pressure evolution of superconductivity and charge-density-wave in kagome superconductor CsV${}_3$Sb${}_5$ thin flakes
• Two types of charge order in the superconducting kagome material CsV${}_3$Sb${}_5$

Cited by in corpus (4)

• AV${}_3$Sb${}_5$ kagome superconductors: a review with transport measurements
• Topological electronic structure and electronic nematicity in candidate kagome superconductors, ATi${}_3$Bi${}_5$ (A = Rb, Cs)
• Superconducting dome and structural changes in LaRu${}_3$Si${}_2$ under pressure
• Beyond kagome: $p$-bands in kagome metals