Electrical and thermal properties for p-type /spl beta/-FeSi/sub 2/ with Mn and Al double doping

Abstract

p-type /spl beta/-FeSi/sub 2/ doped with Mn and Al was prepared by hot pressing in order to examine the effect of double doping effect on electrical resistivity and thermal conductivity. The Hall coefficient as a function of temperature strongly suggested the existence of double valence bands, which become more pronounced with increasing Mn content. At low temperature around several ten K, an anomalous Hall effect has been observed. It becomes more pronounced and the transition temperature from anomalous non-linear Hall voltage as a function of magnetic induction to normal behavior shifts to higher temperature with increasing Mn content. Thermal conductivity /spl kappa/ for Fe/sub 0.936/Mn/sub 0.064/Al/sub 0.015/Si/sub 1.988/ was 0.048 W/cmK at 900 K, which is 13% lower than that of Fe/sub 0.915/Mn/sub 0.085/Si/sub 2/. Thus, it has been shown that alloying effect by double doping is considerably useful for reduction of K.