Investigation of the vortex confinement mechanisms in melt-textured YBa2Cu3O7-x with ion-induced surface nanostructuring

Citation
L. Gozzelino et al., Investigation of the vortex confinement mechanisms in melt-textured YBa2Cu3O7-x with ion-induced surface nanostructuring, PHIL MAG B, 80(5), 2000, pp. 1025-1038
Citations number
25
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICSELECTRONIC OPTICAL AND MAGNETIC PROPERTIES
ISSN journal
13642812 → ACNP
Volume
80
Issue
5
Year of publication
2000
Pages
1025 - 1038
Database
ISI
SICI code
1364-2812(200005)80:5<1025:IOTVCM>2.0.ZU;2-V
Abstract
In the present paper the magnetic properties of high-quality melt-textured YBa2Cu3O7-x irradiated with 2 GeV gold ions are studied. The irradiation af fects a surface layer of 50 mu m (about 10% of the whole sample thickness), while linearly correlated columnar defects are estimated to be present up to about 46 mu m. The paper is focused on the magnetic property analysis of the material before and after irradiation, as determined by the competitio n and/or correlation between surface columnar defects and intrinsic defects . In the intermediate- and high-temperature regions (T > 45 K), the surface columnar defects are very effective according to critical current density J(c), pinning force F-p, creep rate and irreversibility line measurements. In particular the detailed study of the F-p versus B curves at 75 K by mean s of a modified Dew-Hughes model shows that, before and after irradiation, several kinds of defect are effective in different field ranges. After irra diation, the columnar defects greatly modify the full scenario near an acco mmodation field lower than the dose equivalent field. This large effect cou ld depend on the fact that, at least at higher temperatures, the strong pin ning of the vortices in the surface layers induces easier confinement of th e vortices trapped by volume and planar defects in deeper layers.