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Room-Temperature Plasticity of a Nanosized GaN Crystal.

ABSTRACT: GaN wurtzite crystal is commonly regarded as eminently brittle. However, our research demonstrates that nanodeconfined GaN compressed along the M direction begins to exhibit room-temperature plasticity, yielding a dislocation-free structure despite the occurrence of considerable, irreversible deformation. Our interest in M-oriented, strained GaN nanoobjects was sparked by the results of first-principles bandgap calculations, whereas subsequent nanomechanical tests and ultrahigh-voltage (1250 kV) transmission electron microscopy observations confirmed the authenticity of the phenomenon. Moreover, identical experiments along the C direction produced only a quasi-brittle response. Precisely how this happens is demonstrated by molecular dynamics simulations of the deformation of the C- and M-oriented GaN frustum, which mirror our nanopillar crystals.

SUBMITTER: Fujikane M

PROVIDER: S-EPMC8397389 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Room-Temperature Plasticity of a Nanosized GaN Crystal.

Fujikane Masaki M Nagao Shijo S Chrobak Dariusz D Yokogawa Toshiya T Nowak Roman R

Nano letters 20210727 15

GaN wurtzite crystal is commonly regarded as eminently brittle. However, our research demonstrates that nanodeconfined GaN compressed along the M direction begins to exhibit room-temperature plasticity, yielding a dislocation-free structure despite the occurrence of considerable, irreversible deformation. Our interest in M-oriented, strained GaN nanoobjects was sparked by the results of first-principles bandgap calculations, whereas subsequent nanomechanical tests and ultrahigh-voltage (1250 kV) ...[more]

PMID: 34313133

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