Eur. Phys. J. B 33, 25-30 (2003)
https://doi.org/10.1140/epjb/e2003-00137-0

Superconductivity of SrTiO_3-δ

Institute of Physics, Johannes Gutenberg University, 55099 Mainz, Germany

Corresponding author: ^a jourdan@uni-mainz.de

Received: 4 December 2002
Revised: 10 March 2003
Published online: 23 May 2003

Abstract

Superconducting SrTiO_3-δ was obtained by annealing single crystalline SrTiO₃ samples in ultra high vacuum. An analysis of the V(I) characteristics revealed very small critical currents which can be traced back to an unavoidable doping inhomogeneity. R(T) curves were measured for a range of magnetic fields B at , thereby probing only the sample regions with the highest doping level. The resulting curves show upward curvature, both at small and strong doping. These results are discussed in the context of bipolaronic and conventional superconductivity with Fermi surface anisotropy. We conclude that the special superconducting properties of SrTiO_3-δ can be related to its Fermi surface and compare this finding with properties of the recently discovered superconductor MgB₂.