Journal ArticleDOI
Oxygen stoichiometry, structure and superconductivity in Bi2Sr2CaCu2O8+x
Reads0
Chats0
TLDR
In this paper, the influence of oxygen nonstoichimetry on the structure and T c of Bi 2 Sr 2 CaCu 2 O 8+ x (2212) was determined by thermogravimetry.Abstract:
Bi 2 Sr 2 CaCu 2 O 8+ x (2212) was synthesized from freeze-dried precursors. The oxygen content of 2212 was determined as a function of temperature and oxygen partial pressure by thermogravimetry. Four-probe resistivity measurements performed on 2212 confirmed the results of thermogravimetry. The influence of oxygen nonstoichimetry on the structure and T c of 2212 was determined. It was found that 2212 without excess oxygen ( x = 0) is superconducting. This points to the role of the (BiO) ∞ layers as a source for holes in 2212. It was also found that samples of 2212 with the same oxygen content had different T c ′S depending on thermal history, This difference in T c is thought to arise from oxygen occupying different sites in the lattice while maintaining the same total oxygen content. The conclusions are indirectly supported by measurements of the rates of oxygen intercalation and oxygen removal in 2212.read more
Citations
More filters
Journal ArticleDOI
Low energy ion impact-enhanced growth of cubic boron nitride in a supersonic nitrogen/argon plasma flow
Darren Berns,Mark A. Cappelli +1 more
TL;DR: In this article, the growth and analysis of cubic boron nitride films in a low-density, supersonic nitrogen/argon plasma flow into which Boron trichloride gas was injected was described.
Journal ArticleDOI
Oxygen nonstoichiometry, point defects and critical temperature in superconducting oxide Bi2Sr2CaCu2O8+Δ
TL;DR: In this paper, the authors investigated the oxygen nonstoichiometry of the high-T c superconductor Bi 2 Sr 2 CaCu 2 O 8+ Δ by thermogravimetric techniques from 300°C to phase stability limits with oxygen partial pressure ranging from 1 to 10 −4 atm.
Journal ArticleDOI
Growth, contacting and ageing of superconducting Bi-2212 whiskers
M. Truccato,G. Rinaudo,C. Manfredotti,Angelo Agostino,Paola Benzi,Paolo Volpe,C. Paolini,Paolo Olivero +7 more
TL;DR: In this article, the growth of highly oriented microscopic whisker-like crystals in the Bi-Sr-Ca-Cu-O system by means of glassy precursors has been studied.
Journal ArticleDOI
The effect of cooling rates on transport current properties and the critical temperature of Ag-sheathed BSCCO-2223 superconducting tapes
TL;DR: In this article, the transport current properties of Ag-sheathed BSCCO-2223 superconducting tapes were analyzed as a function of cooling rate, and the effect of the lattice parameter on was investigated.
Journal ArticleDOI
Oxygen content and superconducting properties of Hg-based superconductors synthesized by sol-gel method
TL;DR: In this article, the superconducting properties and structural changes of HgBa2CaCu2O6+δ and Hg Ba2Ca2Cu3O8+ δ systems synthesized by the sol-gel method were studied as a function of post-annealing in oxygen flow using thermogravimetric, X-ray diffraction and magnetic susceptibility studies.
References
More filters
Journal ArticleDOI
Superconducting phase of La2CuO4-y: Superconducting composition resulting from phase separation.
James D. Jorgensen,Bogdan Dabrowski,Shiyou Pei,D. G. Hinks,L. Soderholm,Bruno Morosin,J. E. Schirber,Eugene L. Venturini,David S. Ginley +8 more
TL;DR: Neutron-diffraction measurements as a function of temperature show that the phase separation occurs reversibly near 320 K.
Journal ArticleDOI
Models for the modulation in A2B2CanCu1+nO6+2n, A, B=Bi, Sr OR Tl, Ba and n=0, 1, 2
TL;DR: In this paper, a number of models for the modulation in the title compounds are postulated and the best agreement with experimental data is obtained for the model with extra oxygen in the BiO layers.
Journal ArticleDOI
Effect of oxygen pressure on the orthorhombic-tetragonal transition in the high-temperature superconductor YBa 2 Cu 3 O x
TL;DR: High-resolution in situ x-ray-diffraction measurements were made of the lattice constants of O as it was heated and cooled through the orthorhombic-tetragonal transition at a series of pressures to observe the transition's sharp, continuous, and reversible in temperature and pressure.
Journal ArticleDOI
Electronic band structure of CaBi 2 Sr 2 Cu 2 O 8
TL;DR: La structure de bande du quadratique centre CaBi 2 Sr 2 Cu 2 O 8 est calculee dans une approche de fonctionnelle de densite locale par une methode d'orbitales muffin-tin linearisee avec une approximation de sphere atomique.
Journal ArticleDOI
Stoichiometry of bulk superconducting La2CuO4+δ: A superconducting superoxide?
J. E. Schirber,Bruno Morosin,R.M. Merrill,P.F. Hlava,Eugene L. Venturini,James F. Kwak,P. J. Nigrey,R.J. Baughman,David S. Ginley +8 more
TL;DR: In this paper, a variety of analytical tools have been combined to show that bulk superconducting La2CuO4+δ has a La to Cu ratio of 2.00 (± 0.02) and an oxygen stoichiometry of 4.13 (±0.1).