Structure and stability of threading edge and screw dislocations in bulk GaN

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F15%3A00473050" target="_blank" >RIV/68081723:_____/15:00473050 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1016/j.commatsci.2014.12.013" target="_blank" >http://dx.doi.org/10.1016/j.commatsci.2014.12.013</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.commatsci.2014.12.013" target="_blank" >10.1016/j.commatsci.2014.12.013</a>

Result language

angličtina

Original language name

Structure and stability of threading edge and screw dislocations in bulk GaN

Original language description

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.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BM - Solid-state physics and magnetism

OECD FORD branch

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Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2015

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Computational Materials Science

ISSN

0927-0256

e-ISSN

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Volume of the periodical

99

Issue of the periodical within the volume

MAR

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

8

Pages from-to

195-202

UT code for WoS article

000349680100026

EID of the result in the Scopus database

2-s2.0-84921492083