Author:

Keywords:

lattice, Science & Technology, Technology, Physical Sciences, Materials Science, Multidisciplinary, Physics, Applied, Physics, Condensed Matter, Materials Science, Physics, LATTICE, 02 Physical Sciences, 03 Chemical Sciences, 09 Engineering, Fluids & Plasmas, 34 Chemical sciences, 40 Engineering, 51 Physical sciences

Abstract:

The distribution of vortices at low magnetic fields in single crystals of multiband BaFe2-xNixAs2 (x = 0.1 and x = 0.16) superconductors is studied by Bitter decoration. Highly inhomogeneous vortex patterns, including vortex stripes and vortex clusters, are observed. The origin of these inhomogeneous vortex arrays is likely to be due to strong flux pinning, as suggested by magnetization measurements performed at high fields. Alternative possible scenarios, such as type-1.5 superconductivity due to multiband effect, are also discussed.