2007/10/10 by M. Le Tacon, A. Sacuto, Y. Gallais +3 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.76.144505
published as Phys. Rev. B 76, 144505 (2007) · 7 pages, 6 figures
openalex publication_date 2007/10/10 · arxiv created 2007/10/11 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report electronic Raman scattering measurements on optimally doped YBa2Cu3O_7\ensuremath-\ensuremathδ where Zn or Ni impurities have been substituted by Cu. Using Raman selection rules, we have probed the superconducting gap in the nodal and antinodal regions. We show that under impurity substitutions, the energy of the antinodal peak detected in the superconducting state is not related to the critical temperature Tc and that signatures of superconductivity disappear in the nodal regions. Our experimental findings advocate in favor of gapless arcs around the nodes. The breakdown of the relationship between the antinodal gap amplitude and Tc is discussed in terms of local superconducting gap and pseudogap.