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Anisotropic superconducting properties of aligned MgB2 crystallites

O. F. de Lima·R. A. Ribeiro·M. A. Avila·C. A. Cardoso·A. A. Coelho
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Abstract

Samples of aligned MgB2 crystallites have been prepared, allowing for the first time the direct identification of an upper critical field anisotropy Hc2^{ab}/Hc2^{c}= xi_{ab}/xi_{c} ~ 1.73; with xi_{o,ab} ~ 70 A, xi_{o,c} ~ 40 A, and a mass anisotropy ratio m_{ab}/m_{c} ~ 0.3. A ferromagnetic background signal was identified, possibly related to the raw materials purity.

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O. F. de Lima, R. A. Ribeiro, M. A. Avila, C. A. Cardoso, A. A. Coelho. 2001-05-15. Anisotropic superconducting properties of aligned MgB2 crystallites. https://doi.org/10.1103/physrevlett.86.5974

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