The mobility of individual dislocations in bulk single crystals was studied by using both conventional and intermittent loading techniques. A model was used to link experimental data on dislocation paths to the values of kink displacements under intermittent loading. The experimental data were compared with 2 models which described the interaction of a dislocation with point defects. It was shown that, at low Ge concentrations, Cottrell atmospheres determined the dynamic drag on the dislocation; which gave rise to threshold immobilisation. At higher Ge contents, kink drift along the dislocation line (motion in a field of random forces) occurred.

N.V.Abrosimov, V.Alex, D.V.Dyachenko-Dekov, J.L.Iunin, V.I.Nikitenko, V.I.Orlov, S.N.Rossolenko, W.Schröder: Materials Science and Engineering A, 1997, 234-236, 735-8