Carrier Localization Effects in InGaN/GaN Multiple-Quantum-Wells LED Nanowires: Luminescence Quantum Efficiency Improvement and "Negative" Thermal Activation Energy.

Journal Article (Journal Article)

Two-dimensional InGaN/GaN multiple-quantum-wells (MQW) LED structure was nanotextured into quasi-one-dimensional nanowires (NWs) with different average diameters with a combination approach of Ni nanoislands as mask + dry etching. Such nanotexturing bring out several appealing effects including deeper localization of carriers and significant improvement in quantum efficiency (e.g., from 4.76% of the planar MQW structure to 12.5% of the 160 nm MQW NWs) of light emission in the whole interested temperature range from 4 K to 300 K. With the aid of localized-state ensemble (LSE) luminescence model, the photoluminescence spectra of the samples are quantitatively interpreted in the entire temperature range. In terms of distinctive temperature dependence of photoluminescence from these samples, a concept of "negative" thermal activation energy is tentatively proposed for the MQW NWs samples. These findings could lead to a deeper insight into the physical nature of localization and luminescence mechanism of excitons in InGaN/GaN nanowires.

Full Text

Duke Authors

Cited Authors

  • Bao, W; Su, Z; Zheng, C; Ning, J; Xu, S

Published Date

  • September 2016

Published In

Volume / Issue

  • 6 /

Start / End Page

  • 34545 -

PubMed ID

  • 27686154

Pubmed Central ID

  • PMC5043280

Electronic International Standard Serial Number (EISSN)

  • 2045-2322

International Standard Serial Number (ISSN)

  • 2045-2322

Digital Object Identifier (DOI)

  • 10.1038/srep34545


  • eng