skip to main content

SciTech ConnectSciTech Connect

Title: Temperature evolution of carrier dynamics in GaN{sub x}P{sub y}As{sub 1−y−x}alloys

The temperature dependence of carrier dynamics in GaN{sub x}As{sub 1−y}P{sub y} alloys has been investigated by time resolved photoluminescence. This investigation has shown that the decay time constant does not change significantly up to 100 K, and then starts to decrease rapidly above this temperature. Additionally, the decay times at the high-energy side of the spectrum decrease faster than those at the low-energy side. The effects have been explained by the interplay between carrier capture by radiative and nonradiative recombination centers. Detailed simulations show that the effect of carrier localization in the investigated materials is better described by double-scale potential fluctuations that are related to (i) distribution of localized states energy and (ii) bandgap fluctuations. In addition, it was observed that the increase in nitrogen concentration leads to a shorter decay time at room temperature, which is attributed to a larger concentration of non-radiative recombination centers. Furthermore, a post-growth annealing step leads to a longer decay time at room temperature, which is attributed to a reduction in non-radiative recombination centers. At low temperatures, the role of non-radiative centers is suppressed, and therefore the decay time does not differ significantly for samples with either different nitrogen concentrations or in both the as-grownmore » and annealed samples.« less
Authors:
; ;  [1] ;  [1] ;  [2] ;  [3] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [3]
  1. Laboratory for Optical Spectroscopy of Nanostructures, Department of Experimental Physics, Wroclaw University of Technology, Wybrzeze, Wyspianskiego 27, 50-370 Wroclaw (Poland)
  2. (United States)
  3. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
  4. (Hong Kong)
  5. Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States)
  6. Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States)
Publication Date:
OSTI Identifier:
22403015
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 17; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTROSCOPY; ANNEALING; ARSENIDES; CHARGE CARRIERS; COMPUTERIZED SIMULATION; CONCENTRATION RATIO; FLUCTUATIONS; GALLIUM NITRIDES; NITROGEN; PHOSPHIDES; PHOTOLUMINESCENCE; POTENTIALS; RECOMBINATION; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0273-0400 K; TIME RESOLUTION; X-RAY SPECTROSCOPY