Synthesis, characterization and superconducting behavior of the phases (i) Y2-xBaxCu2O5 (0\leqslantx\leqslant1.6) and (ii) YBa2Cu3CxO7Cy (0\leqslantx\leqslant2.0) are reported. The composition YBa2Cu4O7Cy shows a Tc (zero resistance) of 94K. © 1987 The Japan Society of Applied Physics.

Upadhyayula V Varadaraju

Department Of Chemistry

K. Antony Thomas

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Superconductivity Studies on the HighTcPhase in the Y–Ba–Cu–O System

Japanese Journal of Applied Physics

The oxygen-deficient phase of the high Tc superconductor, YBa2Cu3O7, was oxygen-enriched using the fluidization technique to give good superconducting properties. The normal method of oxygen treatment at 900°C for 24 h and at 600°C for 24 h has been reduced to just one treatment at 600°C for 12 h by the fluidization technique to achieve almost the same strength of superconducting signal for the YBa2Cu3O7 powder, which establishes the attractiveness of the latter route for the large-scale preparation of superconducting material. The particle sizes were in the range 0-90, 90-180 and 180-420 μm. The fluidized particles were crystalline with orthorhombic distortion. Tconset, estimated using the a.c. magnetic susceptibility method, was 91·3 K. The volume fraction of superconducting material in the product was 83·7-85·3%, one of the highest values reported so far for YBa2Cu3O7. © 1989 Indian Academy of Sciences.

Journal	Japanese Journal of Applied Physics
ISSN	00214922
Open Access	No