A New Non-Cu-Oxide Superconductor: (Sr1-xLnx)Nb2O6-y (Ln: La, Nd, Pr and Ce)

Abstract
A new non-Cu superconductor (Sr1-x Ln x )Nb2O6-y (Ln: La, Nd, Pr, Ce, Gd and Ho) has been found through resistivity and magnetization measurements. The highest onset transition temperature is about 12 K. Preliminary electron and X-ray diffraction experiments indicate that the crystal structure of the system is orthorhombic with a unit cell of a=11.00 Å, b=7.68 Å and c=5.59 Å, suggesting that the basic crystal structure is an oxygen-deficient CaTa2O6-type structure.