Free charges: Versus excitons: Photoluminescence investigation of InGaN/GaN multiple quantum well nanorods and their planar counterparts
Chen W, Wen X, Yang J, Latzel M, Patterson R, Huang S, Shrestha S, Jia B, Moss DJ, Christiansen S, Conibeer G (2018)
Publication Type: Journal article
Publication year: 2018
Journal
Book Volume: 10
Pages Range: 5358-5365
Journal Issue: 11
DOI: 10.1039/c7nr07567g
Abstract
InGaN/GaN multiple quantum well (MQW) nanorods have demonstrated significantly improved optical and electronic properties compared to their planar counterparts. However, the exact nature of the processes whereby nanorod structures impact the optical properties of quantum wells is not well understood, even though a variety of mechanisms have been proposed. We performed nanoscale spatially resolved, steady-state, and time-resolved photoluminescence (PL) experiments confirming that photoexcited electrons and holes are strongly bound by Coulomb interactions (i.e., excitons) in planar MQWs due to the large exciton binding energy in InGaN quantum wells. In contrast, free electron-hole recombination becomes the dominant mechanism in nanorods, which is ascribed to efficient exciton dissociation. The nanorod sidewall provides an effective pathway for exciton dissociation that significantly improves the optical performance of InGaN/GaN MQWs. We also confirm that surface treatment of nanorod sidewalls has an impact on exciton dissociation. Our results provide new insights into excitonic and charge carrier dynamics of quantum confined materials as well as the influence of surface states.
Involved external institutions
University of New South Wales (UNSW)
Australia (AU)
Max-Planck-Institut für die Physik des Lichts (MPL) / Max Planck Institute for the Science of Light
Germany (DE)
Swinburne University of Technology
Australia (AU)
Australia (AU)
Max-Planck-Institut für die Physik des Lichts (MPL) / Max Planck Institute for the Science of Light
Germany (DE)
Swinburne University of Technology
Australia (AU)
How to cite
APA:
Chen, W., Wen, X., Yang, J., Latzel, M., Patterson, R., Huang, S.,... Conibeer, G. (2018). Free charges: Versus excitons: Photoluminescence investigation of InGaN/GaN multiple quantum well nanorods and their planar counterparts. Nanoscale, 10(11), 5358-5365. https://doi.org/10.1039/c7nr07567g
MLA:
Chen, Weijian, et al. "Free charges: Versus excitons: Photoluminescence investigation of InGaN/GaN multiple quantum well nanorods and their planar counterparts." Nanoscale 10.11 (2018): 5358-5365.
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