Period-Doubled Structure for the 90± Partial Dislocation in Silicon
نویسندگان
چکیده
J. Bennetto,1 R. W. Nunes,2 and David Vanderbilt1 1Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08855-0849 2Complex System Theory Branch, Naval Research Laboratory, Washington, D.C., 20375-53459 and Institute for Computational Sciences, George Mason University, Fairfax, Virginia 20375–5345 (Received 3 April 1997) We suggest that the commonly accepted core structure of the 90± partial dislocation in Si may not be correct, and propose instead a period-doubled structure. We present local-density approximation, tightbinding, and classical Keating-model calculations, all of which indicate that the period-doubled structure is lower in energy. The new structure displays a broken mirror symmetry in addition to the period doubling, leading to a wide variety of possible solitonlike defects and kinks. [S0031-9007(97)03552-7]
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