Nucleation of He clusters at111In in metals

Helium has been implanted in copper. Its interaction with¹¹¹In atoms during isochronal annealing is observed by the perturbed angular correlation (PAC) technique. The results reveal that the nucleation of He-clusters at the¹¹¹In site is accompanied by reactions of intrinsic defects. Therefore, in the case of Cu, where the knowledge of intrinsic defects is nearly complete, the successive building-up of He-clusters can be pursued.This work was supported by the Bundesminister für Forschung und Technologie.