Neutron Irradiation of Mg11B2 : From the Enhancement to the Suppression of Superconducting Properties

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

doi:10.1063/1.1880450

arXiv · cond-mat/0411383

Neutron Irradiation of Mg11B2 : From the Enhancement to the Suppression of Superconducting Properties

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

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Abstract

In this letter we present the effect of neutron irradiation up to fluences of 3.9 1019 n/cm2 on the superconducting properties of MgB2. In order to obtain a disorder structure homogeneously distributed, the experiment was carried out on bulk samples prepared with the 11B isotope. Up to fluences of 1018 n/cm2 the critical temperature is slightly diminished (36 K) and the superconducting properties are significantly improved; the upper critical field is increased from 13.5 T to 20.3 T at 12 K and the irreversibility field is doubled at 5 K. For larger neutron fluences the critical temperature is suppressed down to 12 K and the superconducting properties come out strongly degraded.

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M. Putti, V. Braccini, C. Ferdeghini, F. Gatti, P. Manfrinetti, D. Marre', A. Palenzona, I. Pallecchi, C. Tarantini, I. Sheikin, H. U. Aebersold, E. Lehmann. 2004-11-15. Neutron Irradiation of Mg11B2 : From the Enhancement to the Suppression of Superconducting Properties. https://doi.org/10.1063/1.1880450

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