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Title: H irradiation effects on the GaAs-like Raman modes in GaAs{sub 1-x}N{sub x}/GaAs{sub 1-x}N{sub x}:H planar heterostructures

The GaAs-like longitudinal optical phonon frequency in two hydrogenated GaAs{sub 1-x}N{sub x}/GaAs{sub 1-x}N{sub x}:H microwire heterostructures—with similar N concentration, but different H dose and implantation conditions—has been investigated by micro-Raman mapping. In the case of GaAs{sub 0.991}N{sub 0.009} wires embedded in barriers where GaAs-like properties are recovered through H irradiation, the phonon frequency in the barriers undergoes a blue shift with respect to the wires. In GaAs{sub 0.992}N{sub 0.008} wires embedded in less hydrogenated barriers, the phonon frequency exhibits an opposite behavior (red shift). Strain, disorder, phonon localization effects induced by H-irradiation on the GaAs-like phonon frequency are discussed and related to different types of N-H complexes formed in the hydrogenated barriers. It is shown that the red (blue) character of the frequency shift is related to the dominant N-2H (N-3H) type of complexes. Moreover, for specific experimental conditions, an all-optical determination of the uniaxial strain field is obtained. This may improve the design of recently presented devices that exploit the correlation between uniaxial stress and the degree of polarization of photoluminescence.
Authors:
; ; ;  [1] ; ; ;  [2] ;  [3] ;  [4] ;  [3]
  1. Dipartimento di Fisica, Università degli studi di Pavia, Via Bassi 6, I-27100 Pavia (Italy)
  2. Dipartimento di Fisica, Sapienza Università di Roma, Piazzale A. Moro 2, I-00185 Roma (Italy)
  3. Laboratorio Nazionale TASC-IOM-CNR, Area Science Park, S.S. 14, Km. 163.5, 34149 Trieste (Italy)
  4. (Italy)
Publication Date:
OSTI Identifier:
22399189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CONCENTRATION RATIO; CORRELATIONS; GALLIUM ARSENIDES; GALLIUM NITRIDES; HETEROJUNCTIONS; HYDROGEN COMPLEXES; HYDROGENATION; IRRADIATION; PHONONS; PHOTOLUMINESCENCE; POLARIZATION; RED SHIFT; STRAINS; STRESSES