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Enhanced flux pinning in neutron irradiated MgB2

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 نشر من قبل Ilaria Pallecchi
 تاريخ النشر 2005
  مجال البحث فيزياء
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We study the effect of neutron irradiation on the critical current density Jc of isotopically pure polycrystalline Mg11B2 samples. For fluences in the range 1017-1018 cm-2, Jc is enhanced and its dependence on magnetic field is significantly improved: we demonstrate that, in this regime, point-like pinning centers are effectively introduced in the system proportionally to the neutron fluence. Instead, for larger fluences, a strong suppression of the critical temperature accompanied by a decrease of both the upper critical field Bc2 and Jc is found.



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