2006/11/17 by Walter Escoffier, W. Escoffier, Escoffier, W. +12
Earth and Planetary Sciences · Materials Science · Physics and Astronomy · #High-pressure geophysics and materials #Iron-based superconductors research #Physics of Superconductivity and Magnetism #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0611458
12 pages, 5 figures; the size of Figure 2 on p. 9 was reduced, as some information on it was lost in original submission
arxiv created 2006/11/17 · arxiv updated 2009/12/01
Multi-quanta, or giant, vortices (GVs) are known to appear in very small superconductors near the superconducting transition due to strong confinement of magnetic flux. Here we present evidence for a new, pinning-related, mechanism for the formation of GVs. Using Bitter decoration to visualise vortices in small Nb disks, we show that confinement in combination with strong disorder causes individual vortices to merge into clusters or even GVs well below Tc and Hc2, in contrast to well-defined shells of individual vortices found in the absence of pinning.