Theoretical study of magnetism in transition-metal-doped TiO2 and TiO2-δ -: art. no. 184425

被引:151
作者
Errico, LA
Rentería, M
Weissmann, M
机构
[1] Natl Univ La Plata, Dept Fis, Inst Fis La Plata, Fac Ciencias Exactas,CONICET, RA-1900 La Plata, Argentina
[2] Comis Nacl Energia Atom, Dept Fis, RA-1429 Buenos Aires, DF, Argentina
关键词
D O I
10.1103/PhysRevB.72.184425
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
In recent years there has been an intense search for room temperature ferromagnetism in semiconductors doped with dilute magnetic impurities, in particular, oxides. In this work we study the structural, electronic, and magnetic properties of doped rutile TiO2 for two different impurity concentrations (25% and 6.25%), considering different distributions of the impurities in the host lattice. Calculations were performed with ab initio methods, assuming that the magnetic impurities substitutionally replace the Ti ions. Our results show that a local magnetic moment appears in the cases of Mn, Fe, and Co impurities, but not in the cases of Ni and Cu impurities. They also show that in the system Ti1-xCoxO2 the magnetic ions align ferromagnetically, while in Ti1-xMnxO2 and Ti1-xFexO2 the antiferromagnetic alignment is energetically favorable. We have also studied the effect of oxygen vacancies, which turned out to be very important. Their presence decreases the energy required to introduce the impurities in the host lattice and reciprocally, the presence of impurities is related to a higher vacancy concentration. The pairs impurity-nearest-neighbor oxygen vacancy seem to be the energetically preferred structures and to produce the highest local magnetic moments. Ni and even Cu impurities acquire magnetic moments in this environment.
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页数:8
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共 43 条
[1]  
ANISIMOV VI, CONDMAT0503625
[2]   FULL-POTENTIAL, LINEARIZED AUGMENTED PLANE-WAVE PROGRAMS FOR CRYSTALLINE SYSTEMS [J].
BLAHA, P ;
SCHWARZ, K ;
SORANTIN, P ;
TRICKEY, SB .
COMPUTER PHYSICS COMMUNICATIONS, 1990, 59 (02) :399-415
[3]  
BLAHA P, 1997, WIEN97
[4]  
Chambers S. A., 2002, Mater. Today, V5, P34, DOI [10.1016/S1369-7021(02)05423-8, DOI 10.1016/S1369-7021(02)05423-8]
[5]   Epitaxial growth and properties of ferromagnetic co-doped TiO2 anatase [J].
Chambers, SA ;
Thevuthasan, S ;
Farrow, RFC ;
Marks, RF ;
Thiele, JU ;
Folks, L ;
Samant, MG ;
Kellock, AJ ;
Ruzycki, N ;
Ederer, DL ;
Diebold, U .
APPLIED PHYSICS LETTERS, 2001, 79 (21) :3467-3469
[6]   Local Co structure in epitaxial CoxTi1-xO2-x anatase -: art. no. 100401 [J].
Chambers, SA ;
Heald, SM ;
Droubay, T .
PHYSICAL REVIEW B, 2003, 67 (10)
[7]   Room-temperature ferromagnetism in (Zn1-xMnx)GeP2 semiconductors -: art. no. 257203 [J].
Cho, SL ;
Choi, SY ;
Cha, GB ;
Hong, SC ;
Kim, Y ;
Zhao, YJ ;
Freeman, AJ ;
Ketterson, JB ;
Kim, BJ ;
Kim, YC ;
Choi, BC .
PHYSICAL REVIEW LETTERS, 2002, 88 (25) :4-257203
[8]   Zener model description of ferromagnetism in zinc-blende magnetic semiconductors [J].
Dietl, T ;
Ohno, H ;
Matsukura, F ;
Cibert, J ;
Ferrand, D .
SCIENCE, 2000, 287 (5455) :1019-1022
[9]   Appearance of room-temperature ferromagnetism in Cu-doped TiO2-δ films -: art. no. 161313 [J].
Duhalde, S ;
Vignolo, MF ;
Golmar, F ;
Chiliotte, C ;
Torres, CER ;
Errico, LA ;
Cabrera, AF ;
Rentería, M ;
Sánchez, FH ;
Weissmann, M .
PHYSICAL REVIEW B, 2005, 72 (16)
[10]   Ab initio study of the magnetic ordering in the semiconductors MnxTi1-xO2, CoxTi1-xO2 and FexTi1-xO2 [J].
Errico, LA ;
Weissmann, M ;
Rentería, M .
PHYSICA B-CONDENSED MATTER, 2004, 354 (1-4) :338-340