The preparation and magnetic properties of the high Tc-superconductor (2234) Bi1.6Pb0.4Sr2Ca3Cu4O12+y

Coexisting of the Magnetic Ordering and Superconductivity in a Fluorine and Iodine Dopped Bismut-2234 HTSC

“…Bunda V.V. et al [3,4] and Palatnik L.S. et al [5,6] For the Bi 1.6 Pb 0.4 Sr 2 Ca 3 Cu 4 O 12−z F z samples with fluorine concentration z < 0.25 the superconducting transition is observed in the temperature region 110-132 K [6].…”

“…The value of magnitude of external magnetic field was smaller as a 2.5 mT. The first superconducting transition at T c1 ∼ 108 K we connected with the γ-modification of bismuth-2234 HTSC phase [3,4,6]. From our point of view the second "low-T c " superconducting phase at T c2 ∼ 65 K has the composition Bi 2−x Sr 2+x Ca 1+y Cu 2−y O w (with x =0.3-0.5; y =0.4-0.5 and w ∼ 8), pseudo-tetragonal crystalline cell (a = b = 5.42Å; c =27.65-28.3Å; space group P4/nmm) and disordered crystalline structure.…”