skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy

Abstract

The optical properties of Al-rich AlGaN/AlN quantum wells are assessed by excitation-power-dependent time-integrated (TI) and time-resolved (TR) photoluminescence (PL) measurements. Two excitation sources, an optical parametric oscillator and the 4th harmonics of a Ti:sapphire laser, realize a wide range of excited carrier densities between 10{sup 12} and 10{sup 21 }cm{sup −3}. The emission mechanisms change from an exciton to an electron-hole plasma as the excitation power increases. Accordingly, the PL decay time is drastically reduced, and the integrated PL intensities increase in the following order: linearly, super-linearly, linearly again, and sub-linearly. The observed results are well accounted for by rate equations that consider the saturation effect of non-radiative recombination processes. Using both TIPL and TRPL measurements allows the density of non-radiative recombination centers, the internal quantum efficiency, and the radiative recombination coefficient to be reliably extracted.

Authors:
; ; ; ;  [1]
  1. Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510 (Japan)
Publication Date:
OSTI Identifier:
22413145
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 7; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ALUMINIUM NITRIDES; CARRIER DENSITY; ELECTRONS; EMISSION SPECTROSCOPY; EXCITATION; EXCITONS; GALLIUM NITRIDES; HOLES; OPTICAL PROPERTIES; PARAMETRIC OSCILLATORS; PHOTOLUMINESCENCE; QUANTUM EFFICIENCY; QUANTUM WELLS; REACTION KINETICS; RECOMBINATION; SAPPHIRE; SOLID-STATE PLASMA; TIME RESOLUTION

Citation Formats

Iwata, Yoshiya, Banal, Ryan G., Ichikawa, Shuhei, Funato, Mitsuru, and Kawakami, Yoichi, E-mail: kawakami@kuee.kyoto-u.ac.jp. Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy. United States: N. p., 2015. Web. doi:10.1063/1.4908282.
Iwata, Yoshiya, Banal, Ryan G., Ichikawa, Shuhei, Funato, Mitsuru, & Kawakami, Yoichi, E-mail: kawakami@kuee.kyoto-u.ac.jp. Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy. United States. doi:10.1063/1.4908282.
Iwata, Yoshiya, Banal, Ryan G., Ichikawa, Shuhei, Funato, Mitsuru, and Kawakami, Yoichi, E-mail: kawakami@kuee.kyoto-u.ac.jp. Sat . "Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy". United States. doi:10.1063/1.4908282.
@article{osti_22413145,
title = {Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy},
author = {Iwata, Yoshiya and Banal, Ryan G. and Ichikawa, Shuhei and Funato, Mitsuru and Kawakami, Yoichi, E-mail: kawakami@kuee.kyoto-u.ac.jp},
abstractNote = {The optical properties of Al-rich AlGaN/AlN quantum wells are assessed by excitation-power-dependent time-integrated (TI) and time-resolved (TR) photoluminescence (PL) measurements. Two excitation sources, an optical parametric oscillator and the 4th harmonics of a Ti:sapphire laser, realize a wide range of excited carrier densities between 10{sup 12} and 10{sup 21 }cm{sup −3}. The emission mechanisms change from an exciton to an electron-hole plasma as the excitation power increases. Accordingly, the PL decay time is drastically reduced, and the integrated PL intensities increase in the following order: linearly, super-linearly, linearly again, and sub-linearly. The observed results are well accounted for by rate equations that consider the saturation effect of non-radiative recombination processes. Using both TIPL and TRPL measurements allows the density of non-radiative recombination centers, the internal quantum efficiency, and the radiative recombination coefficient to be reliably extracted.},
doi = {10.1063/1.4908282},
journal = {Journal of Applied Physics},
number = 7,
volume = 117,
place = {United States},
year = {Sat Feb 21 00:00:00 EST 2015},
month = {Sat Feb 21 00:00:00 EST 2015}
}