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Title: Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition

Abstract

By implanting Zn{sup +} ions into research-grade intentionally undoped ZnO single crystal for facilitating Zn interstitials (Zn{sub i}) and O vacancies (V{sub O}) which is revealed by precise X-Ray diffraction rocking curves, we observe an apparent broad red luminescence band with a nearly perfect Gaussian lineshape. This red luminescence band has the zero phonon line at ∼2.4 eV and shows distinctive lattice temperature dependence which is well interpreted with the configurational coordinate model. It also shows a low “kick out” thermal energy and small thermal quenching energy. A “self-activated” optical transition between a shallow donor and the defect center of Zn{sub i}-V{sub O} complex or V{sub Zn}V{sub O} di-vacancies is proposed to be responsible for the red luminescence band. Accompanied with the optical transition, large lattice relaxation simultaneously occurs around the center, as indicated by the generation of multiphonons.

Authors:
; ; ; ;  [1]; ;  [2];  [3]
  1. Department of Physics, HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), HKU-CAS Joint Laboratory on New Materials, The University of Hong Kong, Pokfulam Road, Hong Kong (China)
  2. Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, D-01328 Dresden (Germany)
  3. Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, D-01328 Dresden (Germany)
Publication Date:
OSTI Identifier:
22311193
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 4; 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; DEFECTS; EV RANGE; INTERSTITIALS; LUMINESCENCE; MONOCRYSTALS; NEUTRON DIFFRACTION; PHONONS; QUENCHING; RELAXATION; TEMPERATURE DEPENDENCE; VACANCIES; VISIBLE RADIATION; X-RAY DIFFRACTION; ZINC IONS; ZINC OXIDES

Citation Formats

Chen, Y. N., Xu, S. J., E-mail: sjxu@hku.hk, Zheng, C. C., Ning, J. Q., Ling, F. C. C., Anwand, W., Brauer, G., and Skorupa, W. Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition. United States: N. p., 2014. Web. doi:10.1063/1.4892356.
Chen, Y. N., Xu, S. J., E-mail: sjxu@hku.hk, Zheng, C. C., Ning, J. Q., Ling, F. C. C., Anwand, W., Brauer, G., & Skorupa, W. Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition. United States. doi:10.1063/1.4892356.
Chen, Y. N., Xu, S. J., E-mail: sjxu@hku.hk, Zheng, C. C., Ning, J. Q., Ling, F. C. C., Anwand, W., Brauer, G., and Skorupa, W. Mon . "Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition". United States. doi:10.1063/1.4892356.
@article{osti_22311193,
title = {Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition},
author = {Chen, Y. N. and Xu, S. J., E-mail: sjxu@hku.hk and Zheng, C. C. and Ning, J. Q. and Ling, F. C. C. and Anwand, W. and Brauer, G. and Skorupa, W.},
abstractNote = {By implanting Zn{sup +} ions into research-grade intentionally undoped ZnO single crystal for facilitating Zn interstitials (Zn{sub i}) and O vacancies (V{sub O}) which is revealed by precise X-Ray diffraction rocking curves, we observe an apparent broad red luminescence band with a nearly perfect Gaussian lineshape. This red luminescence band has the zero phonon line at ∼2.4 eV and shows distinctive lattice temperature dependence which is well interpreted with the configurational coordinate model. It also shows a low “kick out” thermal energy and small thermal quenching energy. A “self-activated” optical transition between a shallow donor and the defect center of Zn{sub i}-V{sub O} complex or V{sub Zn}V{sub O} di-vacancies is proposed to be responsible for the red luminescence band. Accompanied with the optical transition, large lattice relaxation simultaneously occurs around the center, as indicated by the generation of multiphonons.},
doi = {10.1063/1.4892356},
journal = {Applied Physics Letters},
number = 4,
volume = 105,
place = {United States},
year = {Mon Jul 28 00:00:00 EDT 2014},
month = {Mon Jul 28 00:00:00 EDT 2014}
}
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