Journal of Nuclear Science, Engineering and Technology (JONSAT)
In cooperation with the Iranian Nuclear Society

Investigation of vacancies effects on the electronic structure of α-Al2O3 crystal

Document Type : Research Paper

Authors

A Alipour 1
A.A Sabouri Dodaran 2
A Shahvar 1

1 Department of Radiation Detection & Dosimetry, Radiation Application Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 31465-1498, Karaj-Iran

2 Department of Physics, Faculty of Science, Payame Noor University, P.O.Box: 19395-3697, Tehran -Iran

https://doi.org/10.24200/nst.2020.1071
Abstract
In this study, the electron structure of the α-Al2O3 rhombohedral graft has been investigated. The alpha-alumina structure belongs to the space group R3c and the rhombohedral with two units of formula (10 atoms) in the primary unit cell. Although the most widely used structure is hexagonal, it consists of 12 aluminum atoms and 18 atomic oxygen units, six units of formulas. The role of defects in the crystalline network, especially the vacancy defect, is investigated in this work. The band structure changes are evaluated in the absence of one of the O or Al atoms. The calculations showed that α-Al2O3 has a direct transition at Γ, and the energy gap obtained from the density functional theory (DFT) method is 6.3 eV. Also, the depletion effect of O is higher than that of Al on the crystal electron structure: α-Al2O3:C, and is useful in increasing the response of this crystal as a detector.

Highlights

 

1. C. Keith, Introduction to Solid State Physics, Solid State, Mercer Center, 251-256 (1969).

2. Hendrik, J. Monkhorst, James, Pack special points for Brillouin-zone integration, Phys. Rew, 13(12), (1976) H.

3. T.V. Perevalov, et al. Electronic Structure of α-Al2O3: Ab Initio Stimulations and Comparison with Experiment, JETP Letters, 85(3), 165-168 (April 2007).

4. H. Salehi, Investigation of the Structure of Energy Bands in α-Al2O3 Crystal Using Basic Principles; Shahid Chamran University of Ahvaz, Journal of Materials Engineering, 2(2) 145-150 (2010).

5. I.I. Oleinik, E. Yu, Tsymbal and D.G.pettifor, Structural of Electronic properties of Co/Al2O3/Co    magnetic tunnel junction from first principle Phys.Rev.B62, 3952 published Aug. (2000).

6. J.M. Dantas, A.F. Lima, M.V. Lalie, Effects of Transition Metal Impurities in alpha Alumina: a Theoretical Study, Journal of Physics, Conf. 249 (1), (2010).

7. Y. Yordshahyan, C. Ruberto, B. Lundqvist, Theoretical Structure Determination of a Complex Material: κ‐Al2O3, J. Am. Ceram, Soc 82 (6) 1365-1380 (2004).

8. W. Tews, R. Gundler, Phys.State.Stat.Sol 109, 255 (1982).

Keywords

Vacancy
α-Al2O3
Density functional theory (DFT)
 
1. C. Keith, Introduction to Solid State Physics, Solid State, Mercer Center, 251-256 (1969).
2. Hendrik, J. Monkhorst, James, Pack special points for Brillouin-zone integration, Phys. Rew, 13(12), (1976) H.
3. T.V. Perevalov, et al. Electronic Structure of α-Al2O3: Ab Initio Stimulations and Comparison with Experiment, JETP Letters, 85(3), 165-168 (April 2007).
4. H. Salehi, Investigation of the Structure of Energy Bands in α-Al2O3 Crystal Using Basic Principles; Shahid Chamran University of Ahvaz, Journal of Materials Engineering, 2(2) 145-150 (2010).
5. I.I. Oleinik, E. Yu, Tsymbal and D.G.pettifor, Structural of Electronic properties of Co/Al2O3/Co    magnetic tunnel junction from first principle Phys.Rev.B62, 3952 published Aug. (2000).
6. J.M. Dantas, A.F. Lima, M.V. Lalie, Effects of Transition Metal Impurities in alpha Alumina: a Theoretical Study, Journal of Physics, Conf. 249 (1), (2010).
7. Y. Yordshahyan, C. Ruberto, B. Lundqvist, Theoretical Structure Determination of a Complex Material: κ‐Al2O3, J. Am. Ceram, Soc 82 (6) 1365-1380 (2004).
8. W. Tews, R. Gundler, Phys.State.Stat.Sol 109, 255 (1982).

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