AN INVESTIGATION OF THE NEW HIGH-TC TL-V-SR-CA-CU-O AND TL-V-SR-CA-Y-CU-O SUPERCONDUCTORS

Superconductivity up to 105K has been achieved in the Tl-V-Sr-Ca-Cu-O and Tl-V-Sr-Ca-Y-Cu-O systems. The partial substitution of vanadium for thallium in the crystal lattice stabilizes the TlSr2CaCu2O7 phase and enhances superconductivity up to 80K. Importantly, 20% of Y3+ replacement of Ca2+ sites in the (Tl,V)Sr2CaCu2O(y) compound reduces the excess hole concentration and increases superconductivity by about 20K.