Superparamagnetism in Co-ion-implanted anatase TiO2 thin films and effects of postannealing

被引：39

作者：

Kim, DH ^{[1
]}

Yang, JS

Kim, YS

Kim, DW

Noh, TW

Bu, SD

Kim, YW

Park, YD

Pearton, SJ

Jo, Y

Park, JG

机构：

[1] Seoul Natl Univ, ReCOE, Seoul 151747, South Korea

[2] Seoul Natl Univ, Sch Phys, Seoul 151747, South Korea

[3] Chonbuk Natl Univ, Dept Phys, Chonju C61756, South Korea

[4] Seoul Natl Univ, Sch Mat Sci & Engn, Seoul 151744, South Korea

[5] Seoul Natl Univ, CSCMR, Seoul 151747, South Korea

[6] Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA

[7] Sungkyunkwan Univ, Dept Phys, Suwon 440746, South Korea

来源：

APPLIED PHYSICS LETTERS | 2003年 / 83卷 / 22期

关键词：

D O I：

10.1063/1.1630841

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We observed superparamagnetism in Co-ion-implanted anatase TiO2 thin films on SrTiO3 (001) substrates. After postannealing under oxygen pressure of 1.0x10(-6) Torr, the blocking temperature increased with increasing annealing temperature. Eventually, the 600 degreesC-annealed sample became ferromagnetic at room temperature. These phenomena can be explained by the formation of Co (or ferromagnetic Co compound) particles and their growth during postannealing, as directly observed with transmission electron microscopy. High oxygen pressure during annealing reduced the size of the clusters and saturation magnetization moment, which indicates that cobalt clustering should be the main cause of the room-temperature ferromagnetism in the Co-ion-implanted films. (C) 2003 American Institute of Physics.

引用

收藏

页码：4574 / 4576

页数：3

相关论文

共 13 条

[1] 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

[2] Clusters and magnetism in epitaxial Co-doped TiO2 anatase [J].

Chambers, SA ;

Droubay, T ;

Wang, CM ;

Lea, AS ;

Farrow, RFC ;

Folks, L ;

Deline, V ;

Anders, S .

APPLIED PHYSICS LETTERS, 2003, 82 (08) :1257-1259

[3] Ferromagnetic properties and structures of the Mn-implanted GaAs semiconductor [J].

Chen, CJ ;

Cai, M ;

Wang, XZ ;

Xu, SF ;

Zhang, M ;

Ding, XM ;

Sun, YX .

JOURNAL OF APPLIED PHYSICS, 2000, 87 (09) :5636-5638

[4] ENHANCED MAGNETIZATION OF NANOSCALE COLLOIDAL COBALT PARTICLES [J].

CHEN, JP ;

SORENSEN, CM ;

KLABUNDE, KJ ;

HADJIPANAYIS, GC .

PHYSICAL REVIEW B, 1995, 51 (17) :11527-11532

[5] Superparamagnetism and magnetic properties of Ni nanoparticles embedded in SiO2 -: art. no. 104406 [J].

Fonseca, FC ;

Goya, GF ;

Jardim, RF ;

Muccillo, R ;

Carreño, NLV ;

Longo, E ;

Leite, ER .

PHYSICAL REVIEW B, 2002, 66 (10) :1044061-1044065

[6] Investigations on the nature of observed ferromagnetism and possible spin polarization in Co-doped anatase TiO2 thin films [J].

Kim, DH ;

Yang, JS ;

Lee, KW ;

Bu, SD ;

Kim, DW ;

Noh, TW ;

Oh, SJ ;

Kim, YW ;

Chung, JS ;

Tanaka, H ;

Lee, HY ;

Kawai, T ;

Won, JY ;

Park, SH ;

Lee, JC .

JOURNAL OF APPLIED PHYSICS, 2003, 93 (10) :6125-6132

[7] Formation of Co nanoclusters in epitaxial Ti0.96Co0.04O2 thin films and their ferromagnetism [J].

Kim, DH ;

Yang, JS ;

Lee, KW ;

Bu, SD ;

Noh, TW ;

Oh, SJ ;

Kim, YW ;

Chung, JS ;

Tanaka, H ;

Lee, HY ;

Kawai, T .

APPLIED PHYSICS LETTERS, 2002, 81 (13) :2421-2423

[8] Roles of the first atomic layers in growth of SrTiO3 films on LaAlO3 substrates [J].

Kim, DW ;

Kim, DH ;

Kang, BS ;

Noh, TW ;

Lee, DR ;

Lee, KB .

APPLIED PHYSICS LETTERS, 1999, 74 (15) :2176-2178

[9] Ferromagnetism induced by clustered Co in Co-doped anatase TiO2 thin films -: art. no. 017401 [J].

Kim, JY ;

Park, JH ;

Park, BG ;

Noh, HJ ;

Oh, SJ ;

Yang, JS ;

Kim, DH ;

Bu, SD ;

Noh, TW ;

Lin, HJ ;

Hsieh, HH ;

Chen, CT .

PHYSICAL REVIEW LETTERS, 2003, 90 (01)

[10] Room-temperature ferromagnetism in transparent transition metal-doped titanium dioxide [J].

Matsumoto, Y ;

Murakami, M ;

Shono, T ;

Hasegawa, T ;

Fukumura, T ;

Kawasaki, M ;

Ahmet, P ;

Chikyow, T ;

Koshihara, S ;

Koinuma, H .

SCIENCE, 2001, 291 (5505) :854-856