Above Room Temperature Ferromagnetism in Si:Mn and TiO2-delta:Co

作者：Granovsky A^*; Orlov A; Perov N; Gan' shina E; Semisalova A; Balagurov L; Kulemanov I; Sapelkin A; Rogalev A; Smekhova A

来源：Journal of Nanoscience and Nanotechnology, 2012, 12(9): 7540-7544.

DOI：10.1166/jnn.2012.6543

• Diluted Magnetic Semiconductors
• Magnetization
• Magneto-Optical Spectra

We present recent experimental results on the structural, electrical, magnetic, and magneto-optical properties of Mn-implanted Si and Co-doped TiO2-delta magnetic oxides. Si wafers, both n- and p-type, with high and low resistivity, were used as the starting materials for implantation with Mn ions at the fluencies up to 5 x 10(16) cm(-2). The saturation magnetization was found to show the lack of any regular dependence on the Si conductivity type, type of impurity and the short post-implantation annealing. According to XMCD Mn impurity in Si does not bear any appreciable magnetic moment at room temperature. The obtained results indicate that above room temperature ferromagnetism in Mn-implanted Si originates not from Mn impurity but rather from structural defects in Si. The TiO2-delta:Co thin films were deposited on LaAlO3 (001) substrates by magnetron sputtering in the argon oxygen atmosphere at oxygen partial pressure of 2.10(-6)-2.10(-4) Torr. The obtained transverse Kerr effect spectra at the visible and XMCD spectra indicate on intrinsic room temperature ferromagnetism in TiO2-delta:Co thin films at low (%26lt;1%) volume fraction of Co.

• 出版日期2012-9