Magneto-superconductivity of 100-atm O2-annealed RuSr2Gd1.5Ce0.5Cu2O<f>10−δ</f>

Studied 100-atm O2-annealed RuSr2Gd1.5Ce0.5Cu2O<f>10−δ</f> (Ru-1222) compound crystallized in a tetragonal I4/mmm space group crystal structure. Thermo-gravimetric (TG) analysis was successfully applied to establish the oxygen content of the sample studied at 9.63 per formula unit. The DC magnetization data (<f>M</f> vs. <f>T</f>) revealed magnetic transition at ∼100 K followed by superconducting transition at ∼40 K. Low field (<f>−100&les;H&les;100</f> Oe) <f>M</f> vs. <f>H</f> hysteresis loop showed a lower critical field (<f>Hc1</f>) value of around 25 Oe. Ferromagnetic component is evidenced at 5, 10, 20 and 40 K. Near saturation field of above 5 T is observed at 5 K. Zero-field returning moment (<f>Mr</f>) and zero-moment coercive field (<f>Hc</f>) values at 5 K are <f>0.35μB</f> and 250 Oe. The resistance vs. temperature (<f>R</f> vs. <f>T</f>) behaviour of the sample confirmed superconductivity at around 43 K. Superconductivity transition (<f>Tc</f>) is broadened under magnetic field with strong granularity like steps. [Copyright &y& Elsevier]