Atmospheric pressure synthesis of Be- and Mg-doped TlBa2Ca2Cu3O10−δ superconductor

We have doped Be and Mg at the Ca sites in TlBa2(Ca2−yMy)Cu3O10−δ superconductors. The improvement of inter-plane coupling is most likely accomplished due to higher electro-negativity and smaller sizes of Be (1.5 Pauling, 1.12 Å) and Mg (1.2 Pauling, 1.6 Å) atoms in comparison with the Ca (1.0 Pauling, 1.97 Å) atom, whereas the suppression of anti-ferromagnetically aligned spins of copper atoms is achieved by making the distribution of carriers optimum and uniform in all CuO2 planes. The influence of enhanced inter-plane coupling and reduced anti-ferromagnetism can be witnessed in the form of increased magnitude of diamagnetism in Be- and Mg-doped TlBa2(Ca2−yMy)Cu3O10−δ samples as compared to un-doped TlBa2Ca2Cu3O10−δ samples. The increase in magnitude of the superconductivity with Be- and Mg-doping in TlBa2(Ca2−yMy)Cu3O10−δ samples is less than that of previously studied Be- and Mg-doped (Cu0.5Tl0.5)Ba2(Ca2−yMy)Cu3O10−δ samples.