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Title: The Hg isoelectronic defect in ZnO

We report a study of the luminescence due to Hg in ZnO, concentrating on the main zero phonon line (ZPL) at 3.2766(1) eV and its associated phonon sidebands. For a sample implanted with radioactive {sup 192}Hg, the ZPL intensity, normalised to that of shallow bound exciton emission, is observed to decrease with an equivalent half-life of 4.5(1) h, very close to the 4.85(20) h half-life of {sup 192}Hg. ZnO implanted with stable Hg impurities produces the same luminescence spectrum. Temperature dependent measurements confirm that the zero phonon line is a thermalizing doublet involving one allowed and one largely forbidden transition from excited states separated by 0.91(1) meV to a common ground state. Uniaxial stress measurements show that the allowed transition takes place from an orbitally degenerate excited state to a non-degenerate ground state in a centre of trigonal (C{sub 3v}) symmetry while the magneto-optical properties are characteristic of electron-hole pair recombination at an isoelectronic defect. The doublet luminescence is assigned to bound exciton recombination involving exchange-split Γ{sub 5} and Γ{sub 1,2} excited states (using C{sub 6v} symmetry labels; Γ{sub 3} and Γ{sub 1,2} using C{sub 3v} labels) at isoelectronic Hg impurities substituting for Zn in the crystal. The electron and holemore » g values deduced from the magneto-optical data indicate that this Hg impurity centre in ZnO is hole-attractive.« less
Authors:
; ;  [1] ;  [2] ;  [3] ; ;  [4] ;  [4] ;  [5]
  1. School of Physical Sciences, National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9 (Ireland)
  2. PH Department, ISOLDE/CERN, 1211 Geneva 23 (Switzerland)
  3. (Germany)
  4. Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund (Germany)
  5. (Russian Federation)
Publication Date:
OSTI Identifier:
22258742
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 114; Journal Issue: 19; Other Information: (c) 2013 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; A CENTERS; CRYSTALS; EXCITED STATES; FORBIDDEN TRANSITIONS; G VALUE; GROUND STATES; HALF-LIFE; HOLES; IMPURITIES; LUMINESCENCE; MERCURY 192; OPTICAL PROPERTIES; PHONONS; RECOMBINATION; TEMPERATURE DEPENDENCE; ZINC OXIDES