A comparison of irradiation effects between neutron and high-energy B-ion irradiation on bulk samples was presented. The transition temperature TC for the neutron irradiation decreased significantly, although the amount of defects was almost the same, of the order of 10−2dpa, for both two cases. This was because the differences of the defect formation process. For the neutron case, mostly damages were originated from nucleus reaction 10B(n,α)7Li. As the result of this, B sites in the crystal structure were affected seriously. This suggests that the B-originated Fermi surfaces were important for the appearance of the superconductivity in MgB2.

A Comparison between B- and n-Irradiation on MgB2 Bulk Samples. S.Okayasu, M.Sataka, H.Ikeda, R.Yoshizaki: Physica C, 2005, 426-431[1], 360-3