Point-Contact Spectroscopy of the Heavy-Fermion Superconductor CeCoIn${}_5$

Abstract

The dynamic conductance of the heavy-fermion superconductor CeCoIn${}_5$ is measured by point-contact spectroscopy as a function of temperature from 60 K down to 400 mK. The contact between the gold tip and the single-crystal is shown to be in the Sharvin limit with the enhanced sub-gap conductance arising from Andreev reflection. The zero-bias conductance data are best fit using the extended Blonder-Tinkham-Klapwijk model with a d-wave superconducting order parameter. A fit to the full conductance curve at 400 mK indicates strong coupling ($2\Delta (0)/k_{\text{B}}{T}_{\text{c}}=4.6$) and quantifies the suppressed Andreev reflection signal, which is a signature of normal-metal/heavy-fermion superconductor junctions. Possibilites for theoretical modeling to account for the suppressed Andreev conductance are suggested.

4 pages, 4 figures, resubmitted to Phys. Rev. Lett

References in corpus (6)

• Fulde-Ferrell-Larkin-Ovchinnikov Superconducting State in CeCoIn5
• The role of critical current on point contact Andreev Reflection spectrum between a normal metal and a superconductor
• Field-angle Dependence of the Zero-Energy Density of States in the Unconventional Heavy-Fermion Superconductor CeCoIn5
• Spectroscopic Evidence for Multiple Order Parameter Components in the Heavy Fermion Superconductor CeCoIn_5
• Hexagonal and Square Flux Line Lattices in CeCoIn5
• Coherent transport in Nb/delta-doped-GaAs hybrid microstructures

Cited by in corpus (36)

• Spin resonance in the d-wave superconductor CeCoIn5
• Nodal Structure of Unconventional Superconductors Probed by the Angle Resolved Thermal Transport Measurements
• A review of two-band superconductivity: materials and effects on the thermodynamic and reversible mixed-state properties
• Andreev Reflection in Heavy-Fermion Superconductors and Order Parameter Symmetry in CeCoIn_5
• Crossover from weak to strong pairing in unconventional superconductors
• Phase Diagram and Spectroscopy of FFLO states of two-dimensional d-wave superconductors
• Anomalous quasiparticle transport in the superconducting state of CeCoIn5
• An Experimental and Semi-Empirical Method to Determine the Pauli-Limiting Field in Quasi 2D Superconductors as applied to $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$: Strong Evidence of a FFLO State
• Coexistence of two order parameters and a pseudogaplike feature in the iron-based superconductor LaFeAsO_(1-x)F_x
• Magnetic field splitting of the spin-resonance in CeCoIn5
• Observation of perfect Andreev reflection due to Klein paradox in a topological superconducting state
• Quantum waveguide theory of Andreev reflection in multiband superconductors: the case of Fe-pnictides
• Field Dependent Coherence Length in the Superclean, High-Kappa Superconductor CeCoIn5
• Point-contact spectroscopy in heavy-fermion superconductors
• Andreev reflection and order parameter symmetry in heavy-fermion superconductors: the case of CeCoIn${}_5$
• Quasiparticles and quantum phase transition in universal low-temperature properties of heavy-fermion metals
• Asymmetric tunneling, Andreev reflection and dynamic conductance spectra in strongly correlated metals
• Structural investigations of CeIrIn${}_5$ and CeCoIn${}_5$ on macroscopic and atomic length scales
• Theory of Scanning Tunneling Spectroscopy: from Kondo Impurities to Heavy Fermion Materials
• Correlation-driven multigap d-wave superconductivity in Anderson lattice model
• Construction of a Cantilever-Andreev-Tunneling rig and its applications to superconductors
• Theory of tunneling spectroscopy in the Larkin-Ovchinnikov state
• Two-channel point-contact tunneling theory of superconductors
• Flat bands and the physics of strongly correlated Fermi systems
• Scanning Tunneling Microscopy studies on CeCoIn${}_5$ and CeIrIn${}_5$
• Comment on "Spectroscopic Evidence for Multiple Order Parameter Components in the Heavy Fermion Superconductor CeCoIn${}_5$"
• Interplane and intraplane heat transport in quasi two-dimensional nodal superconductors
• Andreev reflection spectroscopy of the heavy-fermion superconductor CeCoIn${}_5$ along three different crystallographic orientations
• Spin pumping in d-wave superconductor/ferromagnet hybrids
• Baryon asymmetry resulting from a quantum phase transition in the early universe
• Electron transmission in normal/heavy-fermion superconductor junctions
• Competing order and the asymmetric tunneling spectrum in high temperature cuprate superconductors
• Electron transmission between normal and heavy electron metallic phases in a Kondo lattice system
• Point-contact Andreev reflection spectroscopy of heavy-fermion-metal/superconductor junctions
• Suppressed Andreev Reflection at the Normal-Metal / Heavy-Fermion Superconductor CeCoIn${}_5$ Interface
• Josephson effect in $CeCoI{n}_5$ microbridges as seen via quantum interferometry