Oxygen Knock-Out and Other Studies in α-Irradiated Polycrystalline Bi-2212 Superconductor

Monte Carlo analysis of the oxygen knock-on effects induced by synchrotron x-ray radiation in the Bi2Sr2CaCu2Torsello1, Mino2, Bonino3 et al. 2018Phys. Rev. Materials130110View full textAdd to dashboardCite

“…6). This result is about the double of the Td = 0.073 eV value that was required to explain the oxygen out-diffusion in αirradiation experiments [38][39][40], and also compares favorably to recent DFT calculations showing that a 0.2 eV energy difference exists between the stability points and other relative minima positions for iO atoms in the Bi-O layer [42]. The δ values calculated with the best estimate Td = 0.15 eV are in excellent agreement with the experimental results (see Fig.…”

“…This equation assumes that displaced oxygen atoms can leave the material, or at least can move to some positions where they are electronically inactive. The fact that displaced iO atoms are able to exit Bi-2212 was experimentally confirmed by Bandyopadhyay et al measuring the oxygen content of polycrystalline Bi-2212 samples by means of iodometry after α-irradiation [38][39][40]. Fig.…”

“…According to the authors, this amount of energy simply represents the energy required for the motion of the iO atoms over these space and time scales, including no formation energy of the interstitials. On the other hand, Bandyopadhyay et al [38] [39,40] studied the oxygen out-diffusion induced in polycrystalline Bi-2212 by 40 MeV α-irradiation and showed that by assuming in the TRIM program a binding energy for the iO atoms equal to 0.073 eV it was possible to explain their experimental data by means of the oxygen knock-on process. In order to keep a general validity of our study, we have employed both values to obtain the number density of the displaced atoms.…”

Reduction in Difference of the Resistive and Magnetic Critical Temperature in Irradiated (Bi,Pb)-2223 Superconductors

“…Again there is a defect concentration gradient in the irradiated samples though these are minimised by the both side irradiation. 5,6,9 The small gradient is same in all cases because of same energy of α and targetthickness for all doses. So any effect from this gradient on ∆T c is same for all irradiated samples.…”