support@kaust.edu.sa
+966 (12) 808-3463
  • العربية
logo-black
  • Home
  • People
    • Current
    • Alumni
  • Publications
    • 2021
    • 2020
    • 2019
    • 2018
    • 2017
    • 2016
    • 2015
    • 2014
    • 2013
    • 2012
    • 2011
    • 2010
    • 2009
  • Research
    • Current Research
  • Collaboration
  • News
  • Facilities
  • Join us
  • Contact us
  • Conferences
Semiconductor and Material Spectroscopy Laboratory
breadcrumb-bg

Highly efficient transverse-electric-dominant ultraviolet-c emission employing GaN multiple quantum disks in AlN nanowires matrix

  1. Publications
  • Clear filters

Highly efficient transverse-electric-dominant ultraviolet-c emission employing GaN multiple quantum disks in AlN nanowires matrix

by Ram Chandra Subedi, Jung-Wook Min,, Somak Mitra, Kuang-Hui Li, Idris Ajia, Edgars Stegenburgs, Dalaver H Anjum,, Michele A Conroy, Kalani Moore, Ursel Bangert, Iman S Roqan, Tien Khee Ng, Boon S Ooi
Year: 2021

Abstract

Heavy reliance on extensively studied AlGaN based light emitting diodes (LEDs) to replace environmentally hazardous mercury based ultraviolet (UV) lamps is inevitable. However, external quantum efficiency (EQE) for AlGaN based deep UV emitters remains poor. Dislocation induced nonradiative recombination centers and poor electron-hole wavefunction overlap due to the large polarization field induced quantum confined stark effect (QCSE) in “Al” rich AlGaN are some of the key factors responsible for poor EQE. In addition, the transverse electric polarized light is extremely suppressed in “Al”-rich AlGaN quantum wells (QWs) because of the undesired crossing over among the light hole (LH), heavy hole (HH) and crystal-field split-off (SH) states. Here, optical and structural integrities of dislocation-free ultrathin GaN quantum disk (QDisk) (~ 1.2 nm) embedded in AlN barrier (~ 3 nm) grown employing plasma-assisted molecular beam epitaxy (PAMBE) are investigated considering it as a novel nanostructure to realize highly efficient TE polarized deep UV emitters. The structural and chemical integrities of thus grown QDisks are investigated by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). We, particularly, emphasize the polarization dependent photoluminescence (PL) study of the GaN Disks to accomplish almost purely TE polarized UV (~ 260 nm) light. In addition, we observed significantly high internal quantum efficiency (IQE) of ~ 80 %, which is attributed to the enhanced overlap of the electron-hole wavefunction in extremely quantum confined ultrathin GaN QDisks, thereby presenting GaN …

 

Publisher
SPIE: The International Society for Optics and Photonics

Keywords

Highly efficient transverse-electric-dominant ultraviolet-c emission employing GaN multiple quantum disks in AlN nanowires matrix
logo-white

"KAUST shall be a beacon for peace, hope and reconciliation, and shall serve the people of the Kingdom and the world."

King Abdullah bin Abdulaziz Al Saud, 1924 – 2015

Contact Us

  • +966 (12) 808 4340
  • Iman.roqan@kaust.edu.sa
  • 4700 King Abdullah University of Science and Technology

    Building 3, Level 3

    Thuwal 23955-6900

    Kingdom of Saudi Arabia

Quick links

  • Join us
  • Contact us

© King Abdullah University of Science and Technology. All rights reserved

Privacy Policy
Terms of Use
Loading...