TY - JOUR
T1 - Superconducting properties of high-Jc MgB2 coatings
AU - Christen, D. K.
AU - Cantoni, C.
AU - Thompson, J. R.
AU - Paranthaman, M.
AU - Chisholm, M. F.
AU - Kerchner, H. R.
AU - Christen, H. M.
PY - 2002
Y1 - 2002
N2 - We report the fabrication and superconducting properties of ∼0.5 μm thick, fine-grained polycrystalline coatings of MgB2 on single-crystal substrate surfaces. The films exhibit large critical current densities, implying little effect from the grain boundaries. Analyses for thermal activation effects are inconclusive, and evidence is presented that the irreversibility line is dominated by the combined influences of Hc2 anisotropy and polycrystallinity. Comparative studies of the magnetic persistent currents and electrical transport properties reveal excellent agreement over a wide range of temperature and magnetic field. This result is contrary to similar comparisons on high-temperature cuprates, where disparities arise from the effects of large flux creep and the diverse electric field regimes probed by the two techniques. The MgB2 films exhibit extremely sharp voltage-current relations away from the irreversibility line, in qualitative agreement with observed large Jc values and low rates of magnetic flux creep.
AB - We report the fabrication and superconducting properties of ∼0.5 μm thick, fine-grained polycrystalline coatings of MgB2 on single-crystal substrate surfaces. The films exhibit large critical current densities, implying little effect from the grain boundaries. Analyses for thermal activation effects are inconclusive, and evidence is presented that the irreversibility line is dominated by the combined influences of Hc2 anisotropy and polycrystallinity. Comparative studies of the magnetic persistent currents and electrical transport properties reveal excellent agreement over a wide range of temperature and magnetic field. This result is contrary to similar comparisons on high-temperature cuprates, where disparities arise from the effects of large flux creep and the diverse electric field regimes probed by the two techniques. The MgB2 films exhibit extremely sharp voltage-current relations away from the irreversibility line, in qualitative agreement with observed large Jc values and low rates of magnetic flux creep.
UR - http://www.scopus.com/inward/record.url?scp=0036350262&partnerID=8YFLogxK
M3 - Conference article
AN - SCOPUS:0036350262
SN - 0272-9172
VL - 689
SP - 25
EP - 31
JO - Materials Research Society Symposium - Proceedings
JF - Materials Research Society Symposium - Proceedings
T2 - Materials for High-Temperature Superconductor Technologies
Y2 - 26 November 2001 through 29 November 2001
ER -