Irreversibility Fields and Critical Current Densities in Strongly Pinned YBa2Cu3O7-x Films With Artificial Pinning Centers

The high pressure (50 MPa - 2 GPa) – high temperature synthesized MgB2 bulk materials are characterized by nearly theoretical density (1-2% porosity), 80-98% connectivity, extremely high critical current densities (e.g. at 20 K, in 0–1 T jc=1.3–1.0 MA·cm-2 (with 10% SiC) and jc= 0.92 – 0.73 MA·cm-2 (without doping)), large irreversibility fields (Birr(18.4 K) =15 T and Birr (0 K) = 32.5 T) and high upper critical fields (Bc2 (22 K) =15 T and Bc2(0 K) ~ 42.1 T). The transformation of grain boundary pinning to point pinning in MgB2-based materials with increasing manufacturing temperature (from 800 to 1050 oC) under pressures from 0.1 to 2 GPa correlates well with an increase in critical current density in low external magnetic fields caused by the redistribution of boron and the oxygen impurities in the material structure. As the manufacturing temperature increases, the discontinuous oxygen enriched layers transform into distinct Mg-B-O inclusions and the size and amount of inclusions of higher magnesium borides MgBX (X>4) are reduced. The effect of oxygen and boron redistribution can be enhanced by Ti or SiC additions.

Download Full-text

Critical Current Densities and Irreversibility Fields of HighTcSuperconductors,GaSr2Ca2Cu3O9andBSr2Can-1CunO2n+3(n=3, 4)

Japanese Journal of Applied Physics ◽

10.1143/jjap.35.3378 ◽

1996 ◽

Vol 35 (Part 1, No. 6A) ◽

pp. 3378-3382 ◽

Cited By ~ 7

Author(s):

Shan Yu ◽

Yuichi Okuda ◽

Tetsuya Kawashima ◽

Eiji Takayama-Muromachi

Keyword(s):

Critical Current ◽

Current Densities ◽

Irreversibility Fields

Download Full-text

Effect of heat treatment on critical current density of Nb50Ti composite with artificial pinning centers

Physica C Superconductivity ◽

10.1016/s0921-4534(02)02217-7 ◽

2003 ◽

Vol 386 ◽

pp. 407-410

Author(s):

X.H. Liu ◽

L. Zhou ◽

X.Z. Wu ◽

B.Q. Fu ◽

F.Y. Wang ◽

...

Keyword(s):

Heat Treatment ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Pinning Centers ◽

Artificial Pinning Centers

Download Full-text

Artificial and self-assembled vortex-pinning centers in superconducting Ba(Fe1−xCox)2As2thin films as a route to obtaining very high critical-current densities

Physical Review B ◽

10.1103/physrevb.86.214504 ◽

2012 ◽

Vol 86 (21) ◽

Cited By ~ 32

Author(s):

C. Tarantini ◽

S. Lee ◽

F. Kametani ◽

J. Jiang ◽

J. D. Weiss ◽

...

Keyword(s):

Critical Current ◽

Vortex Pinning ◽

Pinning Centers ◽

Current Densities ◽

Self Assembled ◽

Very High

Download Full-text

YBCO Bulk Superconductors with Sm Addition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.891.483 ◽

2017 ◽

Vol 891 ◽

pp. 483-488 ◽

Cited By ~ 2

Author(s):

Daniela Volochová ◽

Vitaliy Antal ◽

Jozef Kováč ◽

Pavel Diko

Keyword(s):

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Superconducting Properties ◽

Ybco Bulk ◽

Pinning Centers ◽

Bulk Superconductors ◽

Powder Addition ◽

Current Densities ◽

Precursor Powders

The influence of Sm addition on the microstructure and superconducting properties of Y-Ba-Cu-O (YBCO) bulk superconductors has been studied. Precursor powders YBa2Cu3O7-δ (Y-123), Y2O3 and CeO2 were enriched with different amounts of SmBa2Cu3Oy (Sm-123) or Sm2O3 powders with the aim to increase critical current density, Jc,by introducing additional pinning centers. YBCO bulk superconductors with SmBa2Cu3Oy (Y123-Sm) or Sm2O3 (Y123-SmO) powder addition were prepared by the optimized top seeded melt growth process in the form of single grains. Microstructure analysis revealed that Sm2O3 addition leads to a higher amount of smaller Y2BaCuO5 (Y-211) particles, what is related to high critical current densities (Jc ~ 7 x 104 A/cm2) of the YBCO samples with Sm2O3 addition in low magnetic fields. The effect of Sm addition in the form of SmBa2Cu3Oy as well as Sm2O3 powder on Y2BaCuO5 particle size, critical temperature, Tc, and critical current density, Jc, is reported.

Download Full-text