skip to main content

Title: High spatial uniformity of photoluminescence spectra in semipolar (202{sup ¯}1) plane InGaN/GaN quantum wells

Scanning near-field optical spectroscopy was applied to study spatial variations of emission spectra at room temperature in semipolar (202{sup ¯}1) In{sub x}Ga{sub 1−x}N/GaN single quantum wells (QWs) for 0.11≤x≤0.36. Photoluminescence (PL) was found to be highly uniform, with peak wavelength deviations and peak intensity deviations divided by average values in the range of 6–12 meV and 0.03–0.07, respectively. Near-field maps of PL parameters showed large, ∼5 to 10 μm size areas of similar values, as opposed to 100 nm scale variations, often reported for InGaN QWs. The near-field PL spectra were found to broaden with increasing InN molar fraction. In the low In content QWs, the broadening is primarily determined by the random cation distribution, while for larger InN molar fractions 10 nm scale localization sites with increasingly deeper band potentials are suggested as the linewidth broadening cause.
Authors:
 [1] ;  [2] ; ;  [1] ; ; ; ; ;  [3]
  1. Department of Materials and Nano Physics, KTH Royal Institute of Technology, Electrum 229, 16440 Kista (Sweden)
  2. (Lithuania)
  3. Materials Department, University of California, Santa Barbara, California 93106 (United States)
Publication Date:
OSTI Identifier:
22412807
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 2; 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; CATIONS; EMISSION SPECTRA; EMISSION SPECTROSCOPY; GALLIUM NITRIDES; INDIUM COMPOUNDS; INDIUM NITRIDES; LINE BROADENING; LINE WIDTHS; PHOTOLUMINESCENCE; QUANTUM WELLS; RANDOMNESS; TEMPERATURE RANGE 0273-0400 K; VARIATIONS; WAVELENGTHS