Polycrystals of Ba0.5K0.5Fe1.9M 0.1As2 (M = Fe, Co, Ni, Cu, and Zn) synthesized at high pressures show quasi-periodic spikes in the magnetization loop at 2 K owing to successive flux jumps, while the single crystals are observed as absence of jumps. The Zn-doped crystal indicates higher frequency flux jumps than that of Zn-free samples, because of the reduction of grain size and enhancement of grain boundary effect. However, the Co-, Ni- and Cu-doped crystals show less jumps duo to the increased granularity. Our present results suggest that the flux jump in the textured polycrystals is controlled largely by the grain boundary as the flux pining effect rather than the intrinsic dopants.
|Number of pages
|Physica C: Superconductivity and its Applications
|Published - 2013
Bibliographical noteFunding Information:
We thank Drs. M. Miyakawa, D. Johrendt, H.B. Wang, H. Kumakura, H.H. Wen, H. Kontani and J. Yuan for valuable discussions. This research was supported in part by the World Premier International Research Center from MEXT, Grants-in-Aid for Scientific Research (22246083) from JSPS, and the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program) from JSPS.
- Flux jumps
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering