(Cu0.5Tl0.5)Ba2Can−1Cun−yGeyO2n+4−δ (n = 3, 4 and y = 0.5, 0.75, 1.0); superconductors with GeO2 planes

We have successfully synthesized germanium doped (Cu0.5Tl0.5)Ba2Can−1Cun−yGeyO2n+4−δ (n = 3, 4 and y = 0, 0.5, 0.75, 1.0) superconductors and investigated the effect of Ge doping on the superconducting properties of these compounds. The solubility of Ge till y = 1 in the CuO2 planes of (Cu0.5Tl0.5)Ba2Ca2Cu3−yGeyO10−δ, have been found to give superconductivity above 77 K. To our surprise an enhanced superconductivity is observed with the doping of semiconductor germanium in some samples. The enhanced superconductivity associated with mixed CuO2/GeO2 planes can be extremely useful for the understanding of mechanism of superconductivity; since we very well know the properties of germanium based semiconductors.