The effects of aluminum doping for the magnetotransport property of Si:Ce thin films

作者：Shindo D^*; Fujii K; Terao T; Sakurai S; Mori S; Kurushima K; Fujimura N

来源：Journal of Applied Physics, 2010, 107(9): 09C308.

DOI：10.1063/1.3352981

Diluted magnetic semiconductor Ce doped Si films with p-type conduction by means of codoping of Al were fabricated with low-temperature molecular beam epitaxy. The uniformly distributed Ce as a magnetic ion is responsible for the disappearance of ferromagnetic nature. Therefore, the magnetotransport properties of the films were investigated if they have any p-f interaction between f electron in Ce and carrier in this DMS sample. The samples with lower carrier concentration (2 x 10(19) cm(-3) at 80 K) showed variable range hopping (VRH) conduction and VRH induced magnetoresistance (MR) was recognized. Samples with higher carrier concentration (7 x 10(20) cm(-3) at 80 K) showed a metallic conduction and a positive MR. The positive MR is attributed to the quantum correction on the conductivity due to the p-f exchange interaction induced spin splitting of the valence band.

• 出版日期2010-5-1