Počet záznamů: 1
Structure and stability of threading edge and screw dislocations in bulk GaN
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SYSNO ASEP 0473050 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Structure and stability of threading edge and screw dislocations in bulk GaN Tvůrce(i) Gröger, Roman (UFM-A) RID, ORCID
Leconte, L. (FR)
Ostapovets, Andriy (UFM-A) RID, ORCIDCelkový počet autorů 3 Zdroj.dok. Computational Materials Science. - : Elsevier - ISSN 0927-0256
Roč. 99, MAR (2015), s. 195-202Poč.str. 8 s. Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova Threading dislocation ; Edge ; Screw ; GaN Vědní obor RIV BM - Fyzika pevných látek a magnetismus CEP ED1.1.00/02.0068 GA MŠMT - Ministerstvo školství, mládeže a tělovýchovy EE2.3.30.0063 GA MŠMT - Ministerstvo školství, mládeže a tělovýchovy Institucionální podpora UFM-A - RVO:68081723 UT WOS 000349680100026 EID SCOPUS 84921492083 DOI https://doi.org/10.1016/j.commatsci.2014.12.013 Anotace Computational studies of a-type threading edge dislocations parallel to the [0001] direction in bulk GaN reveal three possible structures of their cores that are characterized as the 4-atom ring, the 8-atom ring and the 5/7-atom ring configurations. Similar calculations made on the c-type threading screw dislocation suggest the existence of a full core, although the precise structure is still a matter of debate. Most studies associate the position of the dislocation with only high-symmetry points in the lattice and do not discuss the core stability in non-equiatomic configurations. Here, we investigate how the core structures of a-type edge and c-type screw threading dislocations depend on the position in the (0001) plane at which the dislocation is inserted perpendicular to this plane. Furthermore, by successively removing the high-energy atoms from the cores of these dislocations, we track the stability of each core in non-equiatomic configurations and identify the core structures of minimum energy. The edge dislocation is shown to prefer the 5/7-atom ring structure, while the core of the screw dislocation transforms into a new Ga-rich configuration with the associated energy drop of nearly 0.4 eV per one Angstrom of the dislocation length. For all types of dislocation cores found in this paper, we employ isotropic linear elasticity to estimate their core radii and core energies. Pracoviště Ústav fyziky materiálu Kontakt Yvonna Šrámková, sramkova@ipm.cz, Tel.: 532 290 485 Rok sběru 2017
Počet záznamů: 1