Experimental evidence of s-wave superconductivity in bulk CaC${}_6$

Abstract

The temperature dependence of the in-plane magnetic penetration depth, ${\lambda }_{ab}(T)$, has been measured in a c-axis oriented polycrystalline CaC${}_6$ bulk sample using a high-resolution mutual inductance technique. A clear exponential behavior of ${\lambda }_{ab}(T)$ has been observed at low temperatures, strongly suggesting isotropic s-wave pairing. Data fit using the standard BCS theory yields ${\lambda }_{ab}(0)=(720\pm 80)$ Angstroem and $\Delta (0)=(1.79\pm 0.08)$ meV. The ratio $2\Delta (0)/k_{{}_B}{T}_c=(3.6\pm 0.2)$ gives indication for a conventional weakly coupled superconductor.

To appear in Phys. Rev. Lett

References in corpus (7)

• Superconductivity in the Intercalated Graphite Compounds C6Yb and C6Ca
• Superconductivity of bulk CaC6
• Electronic structure of superconducting graphite intercalate compounds: The role of the interlayer state
• Intercalant-Driven Superconductivity in YbC${}_6$ and CaC${}_6$
• Electronic Collective Modes and Superconductivity in Layered Conductors
• Quantum transport through carbon nanotubes: proximity induced and intrinsic superconductivity
• Granularity-induced gapless superconductivity in NbN films: evidence of thermal phase fluctuations

Cited by in corpus (27)

• Superconducting states of pure and doped graphene
• Anisotropic Electron-Phonon Coupling and Dynamical Nesting on the Graphene Sheets in CaC6
• Superconductivity in Heavy Alkaline-Earths Intercalated Graphites
• Effect of Pressure on Superconducting Ca-intercalated Graphite CaC${}_6$
• Scanning Tunneling Spectroscopy on the novel superconductor CaC6
• Specific Heat of the Ca-Intercalated Graphite Superconductor CaC${}_6$
• Electron-phonon interaction in Graphite Intercalation Compounds
• Electronic structure of superconducting KC${}_8$ and non-superconducting LiC${}_6$ graphite intercalation compounds: Evidence for a graphene-sheet-driven superconducting state
• Superconductivity in graphite intercalation compounds
• Evidence for gap anisotropy in CaC6 from directional point-contact spectroscopy
• Non-adiabatic phonons within the doped graphene layers of XC${}_6$ compounds
• Tight-binding description of intrinsic superconducting correlations in multilayer graphene
• Large Ca Isotope Effect in CaC6
• Unresolved problems in superconductivity of CaC6
• Bulk evidence for single-gap s-wave superconductivity in the intercalated graphite superconductor C${}_6$Yb
• Evidence of Strong-Coupled Superconductivity in CaC6 from Tunneling Spectroscopy
• Nonequilibrium-induced metal-superconductor quantum phase transition in graphene
• Neutron scattering study of the high energy graphitic phonons in superconducting CaC${}_6$
• Far-infrared signature of the superconducting gap in intercalated graphite CaC6
• Electron Spin Dynamics of the Superconductor CaC6 probed by ESR
• Correlated Electronic Structures and the Phase Diagram of Hydrocarbon-based Superconductors
• Muon spin rotation study of the magnetic penetration depth in the intercalated graphite superconductor CaC6
• Challenging the nature of low energy plasmon excitations in CaC${}_6$ using electron energy-loss spectroscopy
• Anisotropic superconductivity in graphite intercalation compound YbC6
• Linear and nonlinear electrodynamic response of bulk CaC6 in the microwave regime
• Theory of Superconductivity in Graphite Intercalation Compounds
• Microwave losses of bulk CaC6