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Title: Efficiency roll-off suppression in organic light-emitting diodes using size-tunable bimetallic bowtie nanoantennas at high current densities

Abstract

Size-tunable bimetallic bowtie nanoantennas have been utilized to suppress the efficiency roll-off characteristics in organic light-emitting diodes (OLEDs) using both the numerical and experimental approaches. The resonant range can be widened by the strong dual-atomic couplings in bimetallic bowtie nanoantennas. Compared with the green OLED with conventional bowtie nanoantennas at a high current density of 800 mA/cm{sup 2}, the measured efficiency roll-off ratio of the OLED with size-modulated bowtie nanoantennas is decreased from 53.2% to 41.8%, and the measured current efficiency is enhanced by 29.9%. When the size-modulated bowtie nanoantennas are utilized in blue phosphorescent OLEDs, the experimental roll-off ratio is suppressed from 43.6% to 25.9% at 250 mA/cm{sup 2}, and the measured current efficiency is also enhanced significantly. It is proposed that the efficiency roll-off suppression is mainly related to the enhanced localized surface plasmon effect, which leads to a shorter radiative lifetime.

Authors:
 [1];  [2];  [3]; ; ; ;  [1];  [2];  [4]; ; ;  [1];  [5]
  1. Key Laboratory of Physical Electronics and Devices of Ministry of Education and Shaanxi Provincial Key Laboratory of Photonics & Information Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)
  2. (China)
  3. (United Kingdom)
  4. Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom)
  5. Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)
Publication Date:
OSTI Identifier:
22590583
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CURRENT DENSITY; CURRENTS; EFFICIENCY; LIFETIME; LIGHT EMITTING DIODES; NANOSTRUCTURES; PLASMONS; SURFACES; VISIBLE RADIATION

Citation Formats

Zhao, Yukun, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, Yun, Feng, E-mail: fyun2010@mail.xjtu.edu.cn, Li, Yufeng, Feng, Lungang, Ding, Wen, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Huang, Yi, Wu, Zhaoxin, Jiao, Bo, Li, Sanfeng, and Zhang, Ye. Efficiency roll-off suppression in organic light-emitting diodes using size-tunable bimetallic bowtie nanoantennas at high current densities. United States: N. p., 2016. Web. doi:10.1063/1.4955129.
Zhao, Yukun, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, Yun, Feng, E-mail: fyun2010@mail.xjtu.edu.cn, Li, Yufeng, Feng, Lungang, Ding, Wen, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Huang, Yi, Wu, Zhaoxin, Jiao, Bo, Li, Sanfeng, & Zhang, Ye. Efficiency roll-off suppression in organic light-emitting diodes using size-tunable bimetallic bowtie nanoantennas at high current densities. United States. doi:10.1063/1.4955129.
Zhao, Yukun, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, Yun, Feng, E-mail: fyun2010@mail.xjtu.edu.cn, Li, Yufeng, Feng, Lungang, Ding, Wen, Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, Huang, Yi, Wu, Zhaoxin, Jiao, Bo, Li, Sanfeng, and Zhang, Ye. 2016. "Efficiency roll-off suppression in organic light-emitting diodes using size-tunable bimetallic bowtie nanoantennas at high current densities". United States. doi:10.1063/1.4955129.
@article{osti_22590583,
title = {Efficiency roll-off suppression in organic light-emitting diodes using size-tunable bimetallic bowtie nanoantennas at high current densities},
author = {Zhao, Yukun and Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 and Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ and Yun, Feng, E-mail: fyun2010@mail.xjtu.edu.cn and Li, Yufeng and Feng, Lungang and Ding, Wen and Solid-State Lighting Engineering Research Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 and Huang, Yi and Wu, Zhaoxin and Jiao, Bo and Li, Sanfeng and Zhang, Ye},
abstractNote = {Size-tunable bimetallic bowtie nanoantennas have been utilized to suppress the efficiency roll-off characteristics in organic light-emitting diodes (OLEDs) using both the numerical and experimental approaches. The resonant range can be widened by the strong dual-atomic couplings in bimetallic bowtie nanoantennas. Compared with the green OLED with conventional bowtie nanoantennas at a high current density of 800 mA/cm{sup 2}, the measured efficiency roll-off ratio of the OLED with size-modulated bowtie nanoantennas is decreased from 53.2% to 41.8%, and the measured current efficiency is enhanced by 29.9%. When the size-modulated bowtie nanoantennas are utilized in blue phosphorescent OLEDs, the experimental roll-off ratio is suppressed from 43.6% to 25.9% at 250 mA/cm{sup 2}, and the measured current efficiency is also enhanced significantly. It is proposed that the efficiency roll-off suppression is mainly related to the enhanced localized surface plasmon effect, which leads to a shorter radiative lifetime.},
doi = {10.1063/1.4955129},
journal = {Applied Physics Letters},
number = 1,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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