Structure, Barriers, and Relaxation Mechanisms of Kinks in the 90 Partial Dislocation in Silicon
نویسندگان
چکیده
R. W. Nunes, J. Bennetto, and David Vanderbilt Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08855-0849 (Received 18 April 1996) Kink defects in the 90± partial dislocation in silicon are studied using a linear-scaling density-matrix technique. The asymmetric core reconstruction plays a crucial role, generating at least four distinct kink species as well as soliton defects. The energies and migration barriers of these entities are calculated and compared with experiment. As a result of certain low-energy kinks, a peculiar alternation of the core reconstruction is predicted. We find the solitons to be remarkably mobile even at very low temperature, and propose that they mediate the kink relaxation dynamics. [S0031-9007(96)00931-3]
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