Eur. Phys. J. B 24, 305-308 (2001)
https://doi.org/10.1007/s10051-001-8678-1

Temperature dependence of the YBa₂Cu₃O₇ energy gap in differently oriented tunnel junctions

¹ 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 cucolo@sa.infn.it

Received: 20 July 2001
Published online: 15 December 2001

Abstract

We have applied the break-junction technique to highly biepitaxial c-axis oriented YBa₂Cu₃O₇ thin films with T_C (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.