Effect of Rare-Earth Oxides Doping on the Superconductivity and Flux Pinning of MgB2 Superconductor

• Published in: Journal of superconductivity and novel magnetism Vol. 24; no. 5; pp. 1611 - 1616
• Main Authors: Pan, X. F., Cheng, C. H., Zhao, Y.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-07-2011; Springer
• Subjects: Borides; Characterization and Evaluation of Materials; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Doping; Exact sciences and technology; Magnesium compounds; Magnetic Materials; Magnetism; Nanomaterials; Nanostructure; Original Paper; Physics; Physics and Astronomy; Properties of type I and type II superconductors; Rare earth compounds; Rare earth metals; Strongly Correlated Systems; Superconductivity; Vortex lattices ,flux pinning, flux creep; Magnetic pinning centers; MgB; Irreversibility field; Flux pinning; Iron oxide; Magnetization; Rare earths Oxides; Doping; Superconductivity; Magnetic moments; Lattice parameters; Precipitates; Impurities; Magnesium boride; Solid state reaction; High-Tc superconductors; ·; Irreversibility line; Flux pining
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-010-1066-4

A series of rare-earth-oxide-doped MgB
2
bulks are prepared by in situ solid-state reaction with Pr
6
O
11
, CeO
2
, Lu
2
O
3
, and Ho
2
O
3
as the dopants. The superconducting properties are investigated and compared with the nano-Fe
3
O
4
doped MgB
2
. It is found that different from doping ferromagnetic nano-Fe
3
O
4
which drastically suppresses superconductivity of MgB
2
, doping the rare-earth-oxides has little effect on superconductivity of MgB
2
although most rare-earth elements have strong magnetic moment. In addition, some boride impurities formed during the reaction between rare-earth oxides and boron can work as effective pinning centers and significantly improve
J
c
and
H
irr
of MgB
2
when these fine nanoboride precipitates (<20 nm) are embedded into the MgB
2
intragrains.