Point-contacts formed by the high-temperature superconductor YBa2Cu3O7−δ prepared by cryochemical technique, and a noble metal (Ag or Cu) are investigated. The maximum value of the energy gap Δ ≃40 meV and the ratio 2Δ/kTc≃12 are obtained. It is found that along certain crystallographic axes of the superconductor under investigation, the electrical resistivity ≲ 10−5 Ω·cm.

Topics
Electrical resistivity, High temperature superconductors, Band gap, Point contacts, Cryogenics
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© 1989 American Institute of Physics.
1989
American Institute of Physics