Evolution of the superconducting energy gap structure concomitant with Fermi surface reconstruction in the heavy-fermion superconductor CeCoIn5

Abstract

The London penetration depth, $\lambda (T)$ was measured in single crystals of Ce${}_{1-x}{R}_x$CoIn${}_5$, $R$=La, Nd and Yb down to 50~mK ($T_c/T\sim$50) using a tunnel-diode resonator. In the cleanest samples $\Delta \lambda (T)$ is best described by the power law, $\Delta \lambda (T)\propto T^n$, with $n\sim 1$, consistent with line nodes. Substitutions of Ce with La, Nd and Yb lead to similar monotonic suppressions of $T_c$, however the effects on $\Delta \lambda (T)$ differ. While La and Nd doping results in an increase of the exponent to $n\sim 2$, as expected for a dirty nodal superconductor, Yb doping leads to $n>3$, inconsistent with nodes, suggesting a change from nodal to nodeless superconductivity where Fermi surface topology changes were reported, implying that the nodal structure and Fermi surface topology are closely linked.

References in corpus (12)

• Magnetic Penetration Depth in Unconventional Superconductors
• Spin resonance in the d-wave superconductor CeCoIn5
• Pairing State with a time-reversal symmetry breaking in FeAs based superconductors
• Lifting of nodes by disorder in extended-$s$ state superconductors: application to ferropnictides
• Andreev Reflection in Heavy-Fermion Superconductors and Order Parameter Symmetry in CeCoIn_5
• Unpaired Electrons in the Heavy-Fermion Superconductor CeCoIn_{5}
• Spectroscopic Evidence for Multiple Order Parameter Components in the Heavy Fermion Superconductor CeCoIn_5
• Nonvanishing Energy Scales at the Quantum Critical Point of CeCoIn5
• Anomalous superfluid density in quantum critical superconductors
• Composition and field tuned magnetism and superconductivity in Nd1-xCexCoIn5
• Resolution of the discrepancy between the variation of the physical properties of Ce1-xYbxCoIn5 single crystals and thin films with Yb composition
• Gapless Fermi Surfaces in anisotropic multiband superconductors in magnetic field

Cited by in corpus (4)

• Robust Upward Dispersion of the Neutron Spin Resonance in the Heavy Fermion Superconductor Ce${}_{1-x}$Yb${}_x$CoIn${}_5$
• Theory of Scanning Tunneling Spectroscopy: from Kondo Impurities to Heavy Fermion Materials
• Spectroscopic Evidence for the Direct Involvement of Local Moments in the Pairing Process of the Heavy-Fermion Superconductor CeCoIn${}_5$
• Pressure studies of the quantum critical alloy Ce(0.93)Yb(0.07)CoIn5