Mixtures of '-Fe γ 4 N/Fe 3 O 4 were prepared from Fe 3 O 4 nano-particles in NH 3 +H 2 mixed gases. By controlling the sintering temperature and time, various samples of (Fe 4 N) x (Fe 3 O 4 ) 1-x with values of x between 0 and 1 were successfully obtained. The magnetization σ and the magnetic parameters of saturation magnetization σ s , remanent magnetization σ r and coercive force H c could be explained by the non-interactive co-existence of '-Fe γ 4 N and Fe 3 O 4 phase in each sample. The temperature and field dependences of the resistivity showed that good tunneling magneto-resistance (TMR) junctions were formed at x = 0.34-0.37 near and below the percolation threshold of x c = 0.4. A large magneto-resistance ratio of -8% was observed for a sample with x = 0.34 at room temperature. The effective TMR barriers in this system are assumed to be γ (or )-Fe α 2 O 3 or Fe n N (n = 2 or 3) in the grain boundaries of Fe
PossibiJities of V and Fe doping into ZnO by mechanical milling of the mixed poWders of ZnO and V 2 0s or y -Fe20 3 were suggested from the results of x-ray powder diffraction measurements. Milled powders of nominal Vo.osZno.9sO did not show the ferromagnetism, but nominal Feo.tZno. 9 0 powders showed room temperature ferromagnetism, suggesting that this system is the diluted magnetic semiq)nductor.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.