2002/09/19 by P. Martinez-Samper, P. Martínez-Samper, H. Suderow +9 · 1 citation
Materials Science · Physics and Astronomy · #Anisotropy #Condensed matter physics #Coupling (piping) #Electron #Fermi surface #Iron-based superconductors research #Materials science #Nickel #Pairing #Phonon #Physics #Quantum mechanics #Quantum tunnelling #Rare-earth and actinide compounds #Scanning tunneling microscope #Scanning tunneling spectroscopy #Superconductivity #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.67.014526
published as Phys. Rev. B 67, 014526 (2003) · 5 pages, 3 figures
arxiv created 2002/09/19 · openalex publication_date 2003/01/29 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present scanning tunneling spectroscopy and microscopy measurements at low temperatures in the borocarbide materials RNi2B2C (R=Y, Lu). The characteristic strong-coupling structure due to the pairing interaction is unambiguously resolved in the superconducting density of states. It is located at the superconducting gap plus the energy corresponding to a phonon mode identified in previous neutron-scattering experiments. These measurements also show that this mode is coupled to the electrons through a highly anisotropic electron-phonon interaction originated by a nesting feature of the Fermi surface. Our experiments, from which we can extract a large electron-phonon coupling parameter \ensuremathλ (between 0.5 and 0.8), demonstrate that this anisotropic electron-phonon coupling has an essential contribution to the pairing interaction. The tunneling spectra show an anisotropic s-wave superconducting gap function.