Spectroscopic evidence for multiple order parameter components in the heavy fermion superconductor CeCoIn5.

Suppressed Andreev Reflection at the Normal-Metal / Heavy-Fermion Superconductor CeCoIn5 Interface

In order to probe the order parameter symmetry of the heavy-fermion superconductor (HFS) CeCoIn5, we employ point-contact spectroscopy, where dynamic conductance spectra are taken from a nano-scale junction between a normal-metal (N) Au tip and a single crystal of CeCoIn5. The point-contact junction (PCJ) is formed on a single crystal surface with two crystallographic orientations, (001) and (1...

Hexagonal and square flux line lattices in CeCoIn5.

Using small-angle neutron scattering, we have imaged the magnetic flux line lattice (FLL) in the d-wave heavy-fermion superconductor CeCoIn5. At low fields we find a hexagonal FLL. Around 0.6 T this undergoes what is most likely a first-order transition to square symmetry, with the nearest neighbors oriented along the gap node directions. This orientation of the square FLL is consistent with th...

Pairing symmetry and two-fluid behavior in the heavy fermion superconductor CeCoIn5

Optical conductivity of the heavy fermion superconductor CeCoIn5

The electrodynamic response of the heavy fermion compound CeCoIn5 is studied via infrared spectroscopy. Below 100 K the high temperature Drude-like conductivity evolves into two distinct components. At low energies a narrow mode is observed which is characteristic of the response of heavy quasiparticles. At higher energies a gap structure emerges with 2D;600 cm ~75 meV!. Examination of the fine...

Exploring the fragile antiferromagnetic superconducting phase in CeCoIn5.

CeCoIn5 is a heavy fermion type-II superconductor showing clear signs of Pauli-limited superconductivity. A variety of measurements give evidence for a transition at high magnetic fields inside the superconducting state, when the field is applied either parallel to or perpendicular to the c axis. When the field is perpendicular to the c axis, antiferromagnetic order develops on the high-field s...