Room temperature ferromagnetic Mn0.026 BX Si0.974-X bulk samples with X=0.001, 0.005, and 0.01 were fabricated by arc melting and followed by thermal annealing at 1000 °C. The effects of carrier density on the ferromagnetism were studied. Due to the high carrier densities, all samples showed metallic behavior. Kondo effect was observed when the temperature was below 10 K. Weakly localized carriers monotonously increased with increasing boron concentration, resulting in the enhancement of exchange coupling among Mn ions. The study indicated that the ferromagnetism originates from the hole mediated Ruderman-Kittel-Kasuya-Yosida mechanism.
ASJC Scopus subject areas
- Physics and Astronomy(all)