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Specific heat of MgB_2 after irradiation

Yuxing Wang·Frederic Bouquet·Ilya Sheikin·Pierre Toulemonde·Bernard Revaz·Michael Eisterer·Harald W. Weber·Joerg Hinderer·Alain Junod
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Abstract

We studied the effect of disorder on the superconducting properties of polycrystalline MgB_2 by specific-heat measurements. In the pristine state, these measurements give a bulk confirmation of the presence of two superconducting gaps with 2 Delta 0 / k_B T_c = 1.3 and 3.9 with nearly equal weights. The scattering introduced by irradiation suppresses T_c and tends to average the two gaps although less than predicted by theory. We also found that by a suitable irradiation process by fast neutrons, a substantial bulk increase of dH_{c2}/dT at T_c can be obtained without sacrificing more than a few degrees in T_c. The upper critical field of the sample after irradiation exceeds 28 T at T goes to 0 K.

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Yuxing Wang, Frederic Bouquet, Ilya Sheikin, Pierre Toulemonde, Bernard Revaz, Michael Eisterer, Harald W. Weber, Joerg Hinderer, Alain Junod. 2003-01-07. Specific heat of MgB_2 after irradiation. https://doi.org/10.1088/0953-8984%2F15%2F6%2F315

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