Minimal Surfaces, Screw Dislocations and Twist Grain Boundaries
نویسنده
چکیده
Large twist-angle grain boundaries in layered structures are often described by Scherk’s first surface whereas small twist-angle grain boundaries are usually described in terms of an array of screw dislocations. We show that there is no essential distinction between these two descriptions and that, in particular, their comparative energetics depends crucially on the core structure of their screw-dislocation topological defects.
منابع مشابه
nd - m at . s of t ] 2 7 A ug 1 99 8 Scherk ’ s First Surface , Twist - Grain - Boundaries and All That
Large twist-angle grain boundaries in layered structures are often described by Scherk's first surface whereas small twist-angle grain boundaries are usually described in terms of an array of screw dislocations. We show that there is no essential distinction between these two descriptions and that, in particular, their comparative energetics depends crucially on the core structure of their scre...
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