Local Mn structure and room temperature ferromagnetism in Mn-doped In2O3 films

Local Mn structure, magnetic, and transport properties in Mn-doped In2O3 films were investigated systematically. The detailed structural analysis and multiple-scattering calculations reveal that Mn2+ ions substitute for In3+ sites of the In2O3 lattice and form MnIn2+ + VO complex with the O vacancy in the nearest coordination shell. All films show clear room temperature ferromagnetism and Mott variable range hopping transport behavior. The saturation magnetization of films increases first, and then decreases with Mn doping, while carrier concentration nc decreases monotonically, implying that the ferromagnetism is not mediated by the charge carriers. These results provide strong evidence that oxygen vacancies play an important role in activating the ferromagnetic interactions in Mn-doped In2O3 films.

[1]  L. Errico,et al.  Theoretical study of magnetism in transition-metal-doped Ti O 2 and Ti O 2 − δ , 2005 .

[2]  H. Ohno,et al.  Making nonmagnetic semiconductors ferromagnetic , 1998, Science.

[3]  Magnetic and transport properties of n-type Fe-doped In2O3 ferromagnetic thin films , 2009, 0905.2083.

[4]  S. Lofland,et al.  Bulk synthesis and high-temperature ferromagnetism of (In1−xFex)2O3−σ with Cu co-doping , 2005 .

[5]  Zhonghua Wu,et al.  Local structure and p–d hybridization of Mn-doped In2O3 films , 2012 .

[6]  L. Errico,et al.  Local structure and magnetic behaviour of Fe-doped TiO2 anatase nanoparticles: experiments and calculations , 2008 .

[7]  I. Takeuchi,et al.  Room temperature ferromagnetic n-type semiconductor in (In1−xFex)2O3−σ , 2005 .

[8]  Room-temperature ferromagnetism via unpaired dopant electrons and p-p coupling in carbon-doped In2O3 : experiment and theory. , 2012 .

[9]  Room temperature ferromagnetism of bulk polycrystalline (In0.85−xSnxFe0.15)2O3: Charge carrier mediated or oxygen vacancy mediated? , 2009 .

[10]  Vacancy mediated room temperature ferromagnetism in Co-doped Dy2O3 , 2012 .

[11]  Chang-Yup Park,et al.  Charge-carrier mediated ferromagnetism in Mo-doped In2O3 films , 2012 .

[12]  Chang-Yup Park,et al.  Room-temperature ferromagnetism observed in Mo-doped indium oxide films , 2009 .

[13]  Xiaohong Xu,et al.  Effects of oxygen vacancy and local spin on the ferromagnetic properties of Ni-doped In2O3 powders , 2012 .

[14]  Yuping Zeng,et al.  Abnormal phase transition and magnetic properties in Cu, Fe co-doped In2O3 nanocrystals , 2008 .

[15]  Mohammed S. Alqahtani,et al.  Room temperature ferromagnetism in metallic and insulating (In1−xFex)2O3 thin films , 2011 .

[16]  Mohammed S. Alqahtani,et al.  Donor-band ferromagnetism in cobalt-doped indium oxide , 2011 .

[17]  Shi Xue Dou,et al.  High temperature ferromagnetism in Ni-doped In2O3 and indium-tin oxide , 2006 .

[18]  Y. Zuo,et al.  Effects of carbothermal annealing on structure defects, electrical and magnetic properties in Fe-doped In2O3 , 2009 .

[19]  H. Koinuma,et al.  Rutile-type oxide-diluted magnetic semiconductor: Mn-doped SnO2 , 2002 .

[20]  Absence of magnetism in Cr-doped In2O3: a case study of phase separation versus phase formation , 2011 .

[21]  Yuchao Yang,et al.  V5+ ionic displacement induced ferroelectric behavior in V-doped ZnO films , 2007 .

[22]  S. N. Dolia,et al.  RETRACTED: “Effect of hydrogenation vs. re-heating on intrinsic magnetization of Co doped In2O3” , 2010 .

[23]  Y. Du,et al.  Ferromagnetism in Tb doped ZnO nanocrystalline films , 2012 .

[24]  M. Amati,et al.  Micro- and Nanopyramids of Manganese-Doped Indium Oxide , 2010 .

[25]  K. Okada,et al.  Ferromagnetism in Transparent Thin Films of Fe-Doped Indium Tin Oxide , 2006 .

[26]  H. Ohno,et al.  Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors , 2000, cond-mat/0007190.

[27]  M. Venkatesan,et al.  Donor impurity band exchange in dilute ferromagnetic oxides , 2005, Nature materials.

[28]  S. Annapoorni,et al.  Oxygen vacancy induced phase formation and room temperature ferromagnetism in undoped and Co-doped TiO2 thin films , 2012 .

[29]  Xiaohong Xu,et al.  Role of carrier and spin in tuning ferromagnetism in Mn and Cr-doped In2O3 thin films , 2010 .

[30]  J. Sakai,et al.  Magnetism due to oxygen vacancies and/or defects in undoped semiconducting and insulating oxide thin films , 2007 .

[31]  M. Venkatesan,et al.  SnO2 doped with Mn, Fe or Co: Room temperature dilute magnetic semiconductors , 2004 .

[32]  C. M. Wang,et al.  Lack of ferromagnetism in n-type cobalt-doped ZnO epitaxial thin films , 2008 .

[33]  Alberto Piqué,et al.  Room temperature ferromagnetism in transparent Fe-doped In2O3 films , 2012 .

[34]  P. Xing,et al.  d0 ferromagnetism in undoped n and p-type In2O3 films , 2012 .

[35]  S. Dou,et al.  Ferromagnetism in Mn-doped In 2O 3 oxide , 2006 .

[36]  S. Dou,et al.  Room-temperature ferromagnetism in Mn and Fe codoped In2O3 , 2006 .

[37]  Xiaoli He,et al.  Synthesis and characterization of room-temperature ferromagnetism in Fe- and Ni-co-doped In2O3 , 2007 .