Temperature dependence of the YBa2Cu3O7 energy gap in differently oriented tunnel junctions
Physics Department and INFM Unit, University of Salerno, Via S.
Allende, 84081 Baronissi (SA), Italy
2 B. Verkin Institute for Low Temperature Physics and Engineering, 47 Lenin Ave, 310164 Kharkov, Ukraine
Corresponding author: a email@example.com
Published online: 15 December 2001
We have applied the break-junction technique to highly biepitaxial c-axis oriented YBa2Cu3O7 thin films with TC (ρ=0) = 91 K. Mechanically adjustable junctions with a good stability and tunneling current favored along the ab-planes have been realized. The conductance characteristics of these junctions show the presence of gap related maxima that move towards zero bias for increasing temperatures. Considering the misorientation angle 45 ± 5 of the junction, a maximum gap value at the Fermi level 22 meV is inferred at T = 13 K. The temperature dependence of the gap related structures, shows a quasilinear behavior for similar to that observed in c-axis oriented, S-I-N type YBa2Cu3O7 planar junctions.
PACS: 74.50.+r – Proximity effects, weak links, tunneling phenomena, and Josephson effects / 74.72.Bk – Y-based cuprates / 74.76.Bz – High-Tc films
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001