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Title: Mn Occupations in Ga1-xMnxN Dilute Magnetic Semiconductors Probed by X-Ray Absorption Near-Edge Structure Spectroscopy

Abstract

X-ray absorption near-edge structure (XANES) is used to study the characteristics of different sites of Mn in the Ga1-xMnxN dilute magnetic semiconductor (DMS) with zinc-blende structure. The XANES spectra of representative Mn occupation sites (substitutional MnGa, interstitial MnI, MnGa-MnI dimer and Mn cluster) in GaN lattice are theoretically calculated and compared with experimental results. The substitutional Mn in GaN is characterized by a pre-edge peak at 2.0 eV and a post-edge multiple-scattering peak at 29.1 eV. The peaks shift in position and drop in intensity dramatically for the interstitial MnI and MnGa-MnI dimmer, and disappear completely for Mn clusters. We propose that the distinct characteristics of Mn K-edge XANES spectra for different Mn sites favor to discriminate Mn occupations in GaMnN DMS.

Authors:
; ; ; ;  [1];  [2];  [3];  [4];  [5]
  1. National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)
  2. Department of Physics, Surface Physics Laboratory (National Key Laboratory), Fudan University, 220 Handan Road, Shanghai 200433 (China)
  3. (China)
  4. Photonics Research Institute, National Institute of Advanced Industrial Science and Technology 1-1-1 Umezono Tsukuba, Ibaraki 305-8568 (Japan)
  5. Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039 (China)
Publication Date:
OSTI Identifier:
21054630
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644530; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; CUBIC LATTICES; DIMERS; EV RANGE; GALLIUM NITRIDES; INTERSTITIALS; MAGNETIC MATERIALS; MAGNETIC SEMICONDUCTORS; MANGANESE COMPOUNDS; MULTIPLE SCATTERING; X-RAY SPECTRA; X-RAY SPECTROSCOPY; ZINC SULFIDES

Citation Formats

Wei Shiqiang, Yan Wensheng, Sun Zhihu, Liu Qinghua, Zhong Wenjie, Zhang Xinyi, Synchrotron Radiation Research Center, Fudan University, 220 Handan Road, Shanghai 200433, Oyanagi, H., and Wu Ziyu. Mn Occupations in Ga1-xMnxN Dilute Magnetic Semiconductors Probed by X-Ray Absorption Near-Edge Structure Spectroscopy. United States: N. p., 2007. Web. doi:10.1063/1.2644530.
Wei Shiqiang, Yan Wensheng, Sun Zhihu, Liu Qinghua, Zhong Wenjie, Zhang Xinyi, Synchrotron Radiation Research Center, Fudan University, 220 Handan Road, Shanghai 200433, Oyanagi, H., & Wu Ziyu. Mn Occupations in Ga1-xMnxN Dilute Magnetic Semiconductors Probed by X-Ray Absorption Near-Edge Structure Spectroscopy. United States. doi:10.1063/1.2644530.
Wei Shiqiang, Yan Wensheng, Sun Zhihu, Liu Qinghua, Zhong Wenjie, Zhang Xinyi, Synchrotron Radiation Research Center, Fudan University, 220 Handan Road, Shanghai 200433, Oyanagi, H., and Wu Ziyu. Fri . "Mn Occupations in Ga1-xMnxN Dilute Magnetic Semiconductors Probed by X-Ray Absorption Near-Edge Structure Spectroscopy". United States. doi:10.1063/1.2644530.
@article{osti_21054630,
title = {Mn Occupations in Ga1-xMnxN Dilute Magnetic Semiconductors Probed by X-Ray Absorption Near-Edge Structure Spectroscopy},
author = {Wei Shiqiang and Yan Wensheng and Sun Zhihu and Liu Qinghua and Zhong Wenjie and Zhang Xinyi and Synchrotron Radiation Research Center, Fudan University, 220 Handan Road, Shanghai 200433 and Oyanagi, H. and Wu Ziyu},
abstractNote = {X-ray absorption near-edge structure (XANES) is used to study the characteristics of different sites of Mn in the Ga1-xMnxN dilute magnetic semiconductor (DMS) with zinc-blende structure. The XANES spectra of representative Mn occupation sites (substitutional MnGa, interstitial MnI, MnGa-MnI dimer and Mn cluster) in GaN lattice are theoretically calculated and compared with experimental results. The substitutional Mn in GaN is characterized by a pre-edge peak at 2.0 eV and a post-edge multiple-scattering peak at 29.1 eV. The peaks shift in position and drop in intensity dramatically for the interstitial MnI and MnGa-MnI dimmer, and disappear completely for Mn clusters. We propose that the distinct characteristics of Mn K-edge XANES spectra for different Mn sites favor to discriminate Mn occupations in GaMnN DMS.},
doi = {10.1063/1.2644530},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
  • A method for the analysis of time-resolved x-ray absorption near edge structure (XANES) spectra is proposed. It combines principal component analysis of the series of experimental spectra, multidimensional interpolation of theoretical XANES as a function of structural parameters, and ab initio XANES calculations. It allows to determine the values of structural parameters for intermediates of chemical reactions and the concentrations of different states as a function of time. This approach is tested using numerically generated data and its possibilities and limitations are discussed. The application of this method to a reaction with methylrhenium trioxide catalyst in solution, for which experimentalmore » data were measured using stopped-flow energy-dispersive x-ray absorption spectroscopy technique, is demonstrated. Possibilities and limitations of this experimental technique are also discussed.« less
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