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Carrier-induced transient defect mechanism for non-radiative recombination in InGaN light-emitting devices.

ABSTRACT: Non-radiative recombination (NRR) of excited carriers poses a serious challenge to optoelectronic device efficiency. Understanding the mechanism is thus crucial to defect physics and technological applications. Here, by using first-principles calculations, we propose a new NRR mechanism, where excited carriers recombine via a Frenkel-pair (FP) defect formation. While in the ground state the FP is high in energy and is unlikely to form, in the electronic excited states its formation is enabled by a strong electron-phonon coupling of the excited carriers. This NRR mechanism is expected to be general for wide-gap semiconductors, rather than being limited to InGaN-based light emitting devices.

SUBMITTER: Bang J

PROVIDER: S-EPMC4830943 | biostudies-other | 2016 Apr

REPOSITORIES: biostudies-other

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