INVESTIGATION OF INTRINSIC POINT-DEFECTS IN RAPIDLY QUENCHED COPPER BY NUCLEAR-QUADRUPOLE DOUBLE-RESONANCE

This letter reports nuclear quadrupole double-resonance (NQDOR) measur ements on Cu specimens that were rapidly quenched from the melt either by Duwez's gun technique or by melt spinning. Comparison with measure ments of the recovery of the residual electrical resistivity and with previous NQDOR studies of electron-irradiated Cu leads to the conclusi on that the defects annealing out in the so-called recovery stage III after low-temperature electron irradiation are self-interstitials. Amo ng the vacancy-type imperfections introduced by the rapid-quenching te chniques employed in the present work there is at least one defect (pr esumably the divacancy) that becomes mobile in the same temperature ra nge as self-interstitials. This is in agreement with the evidence from other work that in Cu the enthalpies of migration of divacancies and of self-interstitials are almost the same.