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Enhancement of Critical Current Density in low level Al-doped MgB2

A. Berenov·A. Serquis·X. Z. Liao·Y. T. Zhu·D. E. Peterson·Y. Bugoslavsky·K. A. Yates·M. G. Blamire·L. F. Cohen·J. L. MacManus-Driscoll
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Abstract

Two sets of MgB2 samples doped with up to 5 at. % of Al were prepared in different laboratories using different procedures. Decreases in the a and c lattice parameters were observed with Al doping confirming Al substitution onto the Mg site. The critical temperature (Tc) remained largely unchanged with Al doping. For 1 - 2.5 at.% doping, at 20K the in-field critical current densities (Jc's) were enhanced, particularly at lower fields. At 5K, in-field Jc was markedly improved, e.g. at 5T Jc was enhanced by a factor of 20 for a doping level of 1 at.% Al. The improved Jcs correlate with increased sample resistivity indicative of an increase in the upper critical field, Hc2, through alloying.

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A. Berenov, A. Serquis, X. Z. Liao, Y. T. Zhu, D. E. Peterson, Y. Bugoslavsky, K. A. Yates, M. G. Blamire, L. F. Cohen, J. L. MacManus-Driscoll. 2004-05-24. Enhancement of Critical Current Density in low level Al-doped MgB2. https://doi.org/10.1088/0953-2048%2F17%2F10%2F001

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