Synthesis, structure, and superconductivity of B-site doped perovskite bismuth lead oxide with indium

Abstract

Many elements can be doped into the A site of perovskite BaBiO₃-based superconductors, but only Bi, Pb, Tl, Sb, Mg, and Na are found in the B site. Here, the successful synthesis of Ba(Bi_0.25Pb_0.75)_1−xIn_xO_3−δ superconductors by solid state reaction provides an example with indium located in the B site. The X-ray, neutron, and selected area electron diffraction data indicate that all the samples crystallize in the non-centrosymmetric space group P1 at room temperature. The superconductive transition temperature T^zero_c of Ba(Bi_0.25Pb_0.75)_1−xIn_xO_3−δ decreases with an increase of indium, which is attributed to the fact that the hole concentration in the samples departs from the optimal hole doping state of BaBi_0.25Pb_0.75O_3−δ superconductor.