Enhanced flux pinning in neutron irradiated MgB2

I. Pallecchi; C. Tarantini; H. U. Aebersold; V. Braccini; C. Fanciulli; C. Ferdeghini; F. Gatti; E. Lehmann; P. Manfrinetti; D. Marre'; A. Palenzona; A. S. Siri; M. Vignolo; M. Putti

doi:10.1103/physrevb.71.212507

arXiv · cond-mat/0506750

Enhanced flux pinning in neutron irradiated MgB2

I. Pallecchi·C. Tarantini·H. U. Aebersold·V. Braccini·C. Fanciulli·C. Ferdeghini·F. Gatti·E. Lehmann·P. Manfrinetti·D. Marre'·A. Palenzona·A. S. Siri·M. Vignolo·M. Putti

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Abstract

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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I. Pallecchi, C. Tarantini, H. U. Aebersold, V. Braccini, C. Fanciulli, C. Ferdeghini, F. Gatti, E. Lehmann, P. Manfrinetti, D. Marre', A. Palenzona, A. S. Siri, M. Vignolo, M. Putti. 2005-06-29. Enhanced flux pinning in neutron irradiated MgB2. https://doi.org/10.1103/physrevb.71.212507

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