2003/12/14 by M. Pissas, D. Stamopoulos, Pissas, M. +5
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Superconductivity (cond-mat.supr-con) #cond-mat.mtrl-sci #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0312350
arxiv created 2003/12/14 · arxiv updated 2009/12/01
We have studied the vortex-matter phase diagram of low C doped MgB2 superconductor. The significant finding is the appearance of a peak effect, which, as both our global magnetization and local ac susceptibility measurements revealed, is placed well below the Hc2-line. The absence of significant bulk pinning below the onset line Hon(T) of the peak effect implies that the Bragg glass phase is present for H < Hon(T). Interestingly, the unexpected absence of bulk pinning above the end point line Hep(T) of the peak effect implies the presence of a slightly pinned vortex phase in the regime Hep(T) < H < Hc2(T). In addition, the observed increase of the Hc2c(0) since the carbon doped MgB2 becomes more dirty and the reduced anisotropy, in comparison to the pure MgB2, makes the C-doped MgB2 more favorable for practical applications.