• J Kurian

      Articles written in Bulletin of Materials Science

    • YBa2SnO5·5, a novel ceramic substrate for YBCO and BiSCCO superconductors

      J Koshy K S Kumar J Kurian Y P Yadava A D Damodaran

      More Details Abstract Fulltext PDF

      YBa2SnO5·5 has been synthesized and sintered as single phase material for its use as substrate for both YBCO and BiSCCO superconductors. YBa2SnO5·5 has a complex cubic perovskite (A2BB’O6) structure with the lattice constanta = 8·430 Å. The dielectric constant and loss factor of YBa2SnO5·5 are in a range suitable for its use as substrate for microwave applications. YBa2SnO5·5 is found to be chemically compatible with both YBCO and BiSCCO superconductors. The thick film of YBCO screen printed on polycrystalline YBa2SnO5·5 substrate gave aTc(0) of 92 K and a critical current density (Jc) of 4 × 104 A/cm2 at 77 K. A screen printed BiSCCO thick film on YBa2SnO5·5 substrate gaveTc(0) = 110 K and current density 3 × 103 A/cm2 at 77 K.

    • Novel ceramic substrates for high Tc superconductors

      J Koshy J Kurian R Jose Asha M John P K Sajith J James S P Pai R Pinto

      More Details Abstract Fulltext PDF

      A group of complex perovskite oxides REBa2NbO6 (RE=La and Dy) have been synthesized and developed for their use as substrates for both YBa2Cu3O7-δ and Bi(2223) superconductors. These materials have a complex cubic perovskite (A2BB′O6) structure with lattice constants,a=8·48−8·60 Å. REBa2NbO6 did not show any phase transition in the temperature range 30–1300°C. The thermal expansion coefficient, thermal diffusivity and thermal conductivity values of REBa2NbO6 are favourable for their use as substrates for highTc superconductors. The dielectric constant and loss factor of REBa2NbO6 are in a range suitable for their use as substrates for microwave applications. Both YBa2Cu3O7-δ and Bi(2223) superconductors did not show any detectable chemical reaction with REBa2NbO6 even under extreme processing conditions. Dip coated YBa2Cu3O7-δ thick films on polycrystalline REBa2NbO6 substrate gave aTc(0) of 92 K and a current density of ∼1·1×104 A/cm2 and Bi(2223) thick film on polycrystalline REBa2NbO6 substrate gave aTc(0) of 110 K and a current density of ∼ 4×103 A/cm2 at 77 K and zero magnetic field. A laser ablated YBa2Cu3O7-δ thin film deposited on polycrystalline REBa2NbO6 substrate gave aTc(0) of 90 K and a current density of ∼5×105 A/cm2.

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    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

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