Radiation Effect of YBa₂Cu₃O_7-y Irradiated by γ-Rays and 14 MeV Neutrons

Abstract

High-T c superconductor YBa2Cu3O7-y was irradiated by γ-rays and 14 MeV neutrons to a dose up to 2.5×109 rad and 2×1015 n/cm2, respectively. No significant effects on the critical temperature were found in these irradiations, but the resistivity at 273 K changed slightly. It was concluded from this experiment that electronic process was not very influential in changing the T c and the effects of 14 MeV neutrons on defect formation were assumed to be comparable to those of inpile neutrons.

Effect of ?-Irradiation on Superconductivity in Polycrystalline YBa2Cu3O7-?

“…3) corresponds to some of the previous studies [11,14], but the general picture of the non-monotonic dependence of T c on radiation dose looks like a surprising thing. I. Belevtsev et al The observed initial T c decrease with g-ray dose (Fig.…”

“…This density, is however, not low enough to expect some significant influence of g-ray irradiation on conductivity and order parameter of HTSCs, and hence, on their T c . [11,14], in some other investigations no change in T c was found at all up to doses of about 1000 MR [13], or found to be much less than 1 K [16,17]. The maximum decrease in T c was found to be about 2 K by high doses of F % 1000 MR [11,14].…”

Point and extended defects in superconductors

“…As discussed in the introduction, the regions of the grains are largely insensitive to γ-rays, while the regions of the grain boundaries of the polycrystalline HTSC material are expected to be very sensitive to γ-irradiation doses, causing either a net enhancement at low doses and might cause a net suppression of the transport properties (mostly at high doses). This result has been confirmed by experiments on HTSCs polycrystals [19] and crystals [34,35]. Thus, we may conclude that the major changes to the critical current density observed in our results are mainly due to the nature of the regions of the grain boundaries combined with their high sensitivity to γ-rays.…”

Methodological, applied and thermodynamic aspects of hydrogen sorption by graphite and related carbon nanostructures

“…Irradiation experiments are effective methods for producing such defects in a rather controlled manner. The irradiation techniques commonly employed involve electrons [11], protons [12], γ rays [13][14][15], neutrons [16] and ions [17]. Of these, γ irradiation is one of the most efficient ways to create homogeneously distributed defects, because of the great penetration capability of γ rays over the whole material, creating localized defects that function as flux-pinning sites.…”