Extended point defects in crystalline materials: Ge and Si.
نویسندگان
چکیده
B diffusion measurements are used to probe the basic nature of self-interstitial point defects in Ge. We find two distinct self-interstitial forms--a simple one with low entropy and a complex one with entropy ∼30 k at the migration saddle point. The latter dominates diffusion at high temperature. We propose that its structure is similar to that of an amorphous pocket--we name it a morph. Computational modeling suggests that morphs exist in both self-interstitial and vacancylike forms, and are crucial for diffusion and defect dynamics in Ge, Si, and probably many other crystalline solids.
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ورودعنوان ژورنال:
- Physical review letters
دوره 110 15 شماره
صفحات -
تاریخ انتشار 2013