Unconventional magnetism in semiconductors: Role of localized acceptor states

被引:69
作者
Dev, Pratibha [1 ]
Zhang, Peihong [1 ]
机构
[1] SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA
关键词
GAN; FERROMAGNETISM; ZNO; TRANSPARENT; VACANCY; ENERGY;
D O I
10.1103/PhysRevB.81.085207
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Magnetism induced by the localized defect states in the otherwise "nonmagnetic" sp semiconductors-GaN and ZnO-is investigated using ab initio methods. The defects studied include the cation vacancy in ZnO, a potassium substitutional in GaN, and an acceptor like defect complex (gallium vacancy along with oxygen as an anion substitutional). In all three cases, spontaneous spin-polarized ground states are obtained within density-functional theory (DFT). Magnetic coupling between defect-induced local moments is also studied by mapping the DFT total energy to a nearest-neighbor Heisenberg model. The coupling between magnetic moments is found to be ferromagnetic for the case of cation vacancies in ZnO. This is also found to be the case for the potassium substitutional in GaN. However, the magnetic coupling is antiferromagnetic for the acceptorlike defect complex. A kinetic exchange model is used to explain this diverse magnetic behavior shown by the different systems.
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页数:9
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共 77 条
[71]   Enhanced ferromagnetic stability in Cu doped passivated GaN nanowires [J].
Xiang, H. J. ;
Wei, Su-Huai .
NANO LETTERS, 2008, 8 (07) :1825-1829
[72]   Structural, optical, and magnetic properties of Cu-implanted GaN films [J].
Yang, X. L. ;
Chen, Z. T. ;
Wang, C. D. ;
Zhang, Y. ;
Pei, X. D. ;
Yang, Z. J. ;
Zhang, G. Y. ;
Ding, Z. B. ;
Wang, K. ;
Yao, S. D. .
JOURNAL OF APPLIED PHYSICS, 2009, 105 (05)
[73]   Exchange integrals of Sr2CuO2Cl2 and Ba2Cu3O4Cl2 from LDA+U calculations -: art. no. 115111 [J].
Yaresko, AN ;
Perlov, AY ;
Hayn, R ;
Rosner, H .
PHYSICAL REVIEW B, 2002, 65 (11)
[74]   Defect-induced magnetism in graphene [J].
Yazyev, Oleg V. ;
Helm, Lothar .
PHYSICAL REVIEW B, 2007, 75 (12)
[75]   Electronic Manifestation of Cation-Vacancy-Induced Magnetic Moments in a Transparent Oxide Semiconductor: Anatase Nb:TiO2 [J].
Zhang, Shixiong ;
Ogale, Satishchandra B. ;
Yu, Weiqiang ;
Gao, Xingyu ;
Liu, Tao ;
Ghosh, Saurabh ;
Das, Gour P. ;
Wee, Andrew T. S. ;
Greene, Richard L. ;
Venkatesan, Thirumalai .
ADVANCED MATERIALS, 2009, 21 (22) :2282-+
[76]   First-principles study of defect-induced magnetism in carbon [J].
Zhang, Y. ;
Talapatra, S. ;
Kar, S. ;
Vajtai, R. ;
Nayak, S. K. ;
Ajayan, P. M. .
PHYSICAL REVIEW LETTERS, 2007, 99 (10)
[77]   Synthesis and photoluminescence of a full zinc blende phase ZnO nanorod array [J].
Zhou, Shao-Min ;
Gong, He-Chun ;
Zhang, Bin ;
Du, Zu-Liang ;
Zhang, Xing-Tang ;
Wu, Si-Xin .
NANOTECHNOLOGY, 2008, 19 (17)