Open AccessEFFECT OF HEAT TREATMENT IN H2 ATMOSPHERE ON Bi2Sr2CaCu2O8+δ
Author(s) -
Fang Minghu,
Xuanjia Zhang,
Z. A. Xu,
Min Shen,
Qirui Zhang,
Wu Yu-Ming,
Qidong Wang,
Xiaoming Tang
Publication year - 1992
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.41.1504
Subject(s) - oxygen , superconductivity , hydrogen , atmosphere (unit) , materials science , reducing atmosphere , atmospheric temperature range , annealing (glass) , diffraction , absorption (acoustics) , analytical chemistry (journal) , phase (matter) , condensed matter physics , chemistry , physics , thermodynamics , optics , metallurgy , organic chemistry , chromatography , composite material
The X-ray powder diffraction, properties of normal state and superconducting state (especially carrier concentration) measurements were carried out for the high quality and single phase polycrystal Bi2Sr2CaCu2O8+δ samples annealed in low vacuum or H2 atmosphere at various temperatures. The results reveal that the oxygen atoms escape for Bi2Sr2CaCu2O8+δ samples annealed in H2 atmosphere is devided into two steps. First, the extra oxygen atoms residing between the Bi-O layers escape, and the carrier concentration of samples decreases, the superconducting transition temperature Tc of samples is modulated. Second, the oxygen atoms in the CuO2 planes are removed, and the oxygen vacancies, which induce the short range 2D-AFM order of Cu2+ to decrease, emerge in the CuO2 planes, We suggest that the variation of Tc led by hydrogen absorption in the Bi2Sr2CaCu2O8+δ superconductor might be mainly brought on by the oxygen content variation in the course of absorbing hydrogen, rather than by the electron dopping effect of hydrogen atoms.