-
提出了W型六角铁氧体BaCoxZn2-xFe16O27的晶体结构模型,并通过基于密度泛函理论 框架下Hubbard参数U修正的广义梯度近似密度泛函理论方法研究了该材料的基态电子结构、磁性和静电介电性特性. Co和Zn共掺杂引起BaFe18O27的导电性从半金属转换到半导体. BaCoxZn2-xFe16O27的能隙随x增加而增加, 晶格常数和原胞磁矩随之而变小.介电常数计算表明, BaCoxZn2-xFe16O27的静电 介电常数随x增加而增加, 在6.2-7.2范围而且显示各向异性. Born电荷计算分析表明Co和Zn本身极化对材料的介电常数和其各向异性影响不大.On the basis of the crystal structure model of BaCoxZn2-xFe16O27 , their ground electronic states and dielectric properties have been investigated using the generalized gradient approximation plus Hubbard U approach. The co-substitutions of cobalt and zinc cause the electrical conductivity of BaFe18O27 to change from a half-metallic to semiconductive. With the increase of Co content x, the energy gap of BaCoxZn2-xFe16O27 increases but the lattice constants and the magnetic moment of the unit cell decrease. The calculations of dielectric constants show that the static dielectric constants increase with x, lie in a range of 6.2-7.2 and appear to be anisotropic. Through the Born electric charge analysis it is shown that the polarization of Co and Zn itself has little effect on the polarization of the material and the main polarization may be related to the polarization of the iron and oxygen ions, caused by the crystal distortion.
-
Keywords:
- W-type hexagonal ferrite /
- first principles /
- electronic structure /
- dielectric properties
[1] Wu Y F, Huang Y, Niu L, Zhang Y L, Li Y Q, Wang X Y 2012 J. Magn. Magn. Mater. 324 616
[2] Deng L W, Ding L, Zhou K S, Huang S X, Hu Z W, Yang B C 2011 J. Magn. Magn. Mater. 323 1895
[3] Muhammad J I, Rafaqat A K, Mizukami S, Miyazaki T 2011 J. Magn. Magn. Mater. 323 2137
[4] Ri C H, Li L, Zhu L 2011 Acta Phys. Sin. 60 107102 (in Chinese) [李忠虎, 李林, 朱林 2011 物理学报 60 107102]
[5] Ri C H, Li L, Qi Y 2012 J. Magn. Magn. Mater. 324 1498
[6] Gorter E W 1957 Proc. IEE. 104B (Suppl) 255
[7] Collomb A, Wolfers P, Obradors X 1986 J. Magn. Magn. Mater. 62 57
[8] Collomb A 1987 Mat. Res. Bull. 22 753
[9] Paoluzi A, Licci F, Moze O, Turilli G, Deriu A, Albanese G, Calabrese E 1988 J. Appl. Phys. 63 5074
[10] Kresse G, Furthmüller J 1996 Phys. Rev. B 54 11169
[11] Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[12] Dudarev S L, Botton G A, Savrasov S Y, Humphreys C J, Sutton A P 1988 Phys. Rev. B 57 1505
[13] Wang L, Maxisch T, Ceder G 2006 Phys. Rev. B 73 195107
[14] Gajdoš M, Hummer K, Kresse G, Furthmüller J, Bechstedt F 2006 Phys. Rev. B 73 045112
[15] Li Z W, Chen L F, Ong C K 2003 J. Appl. Phys. 94 5918
[16] Li Z W, Chen L F, Wu Y P, Ong C K 2004 J. Appl. Phys. 96 534
[17] Zhang H J, Yao X, Zhang L Y 2003 J. Phys. D: Appl. Phys. 36 730
[18] Ghosez P, Michenaud J P, Gonze X 1998 Phys. Rev. B 58 6224
-
[1] Wu Y F, Huang Y, Niu L, Zhang Y L, Li Y Q, Wang X Y 2012 J. Magn. Magn. Mater. 324 616
[2] Deng L W, Ding L, Zhou K S, Huang S X, Hu Z W, Yang B C 2011 J. Magn. Magn. Mater. 323 1895
[3] Muhammad J I, Rafaqat A K, Mizukami S, Miyazaki T 2011 J. Magn. Magn. Mater. 323 2137
[4] Ri C H, Li L, Zhu L 2011 Acta Phys. Sin. 60 107102 (in Chinese) [李忠虎, 李林, 朱林 2011 物理学报 60 107102]
[5] Ri C H, Li L, Qi Y 2012 J. Magn. Magn. Mater. 324 1498
[6] Gorter E W 1957 Proc. IEE. 104B (Suppl) 255
[7] Collomb A, Wolfers P, Obradors X 1986 J. Magn. Magn. Mater. 62 57
[8] Collomb A 1987 Mat. Res. Bull. 22 753
[9] Paoluzi A, Licci F, Moze O, Turilli G, Deriu A, Albanese G, Calabrese E 1988 J. Appl. Phys. 63 5074
[10] Kresse G, Furthmüller J 1996 Phys. Rev. B 54 11169
[11] Perdew J P, Burke K, Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[12] Dudarev S L, Botton G A, Savrasov S Y, Humphreys C J, Sutton A P 1988 Phys. Rev. B 57 1505
[13] Wang L, Maxisch T, Ceder G 2006 Phys. Rev. B 73 195107
[14] Gajdoš M, Hummer K, Kresse G, Furthmüller J, Bechstedt F 2006 Phys. Rev. B 73 045112
[15] Li Z W, Chen L F, Ong C K 2003 J. Appl. Phys. 94 5918
[16] Li Z W, Chen L F, Wu Y P, Ong C K 2004 J. Appl. Phys. 96 534
[17] Zhang H J, Yao X, Zhang L Y 2003 J. Phys. D: Appl. Phys. 36 730
[18] Ghosez P, Michenaud J P, Gonze X 1998 Phys. Rev. B 58 6224
计量
- 文章访问数: 6933
- PDF下载量: 884
- 被引次数: 0