Significant suppression of ferromagnetism by hydrostatic pressure in the diluted magnetic semiconductor Sb_(2-x)V_xTe_3 with x ≤ 0.03

摘要

The authors report on the hydrostatic pressure dependence of the magnetotransport properties of ferromagnetic Sb_(2-x);V_xTe_3 single crystals with x=0.02-0.03. Pressure significantly increases the free hole concentration in these compounds. In turn, the Curie temperature is suppressed by roughly 40%, which goes against many models that would predict an increase in Curie temperature with increasing carrier concentration. These results indicate that the ferromagnetism in these materials is carrier mediated and that a full Ruderman-Kittel-Kasuya-Yosida model that takes into account the oscillatory nature of the indirect exchange interaction among localized spins is needed in order to explain the data.