Electric transport in N-type Fe2O3

Abstract

Resistivity, Seebeck-coefficient, Hall-coefficient and magneto-resistance of n-type single crystal ferric oxide (hematite), containing Sn4+ as an impurity, are reported. The resistivity does not show important anisotropy. The Hall- and magneto-resistance effects are probably related to the parasitic ferromagnetism present in this material, their magnitude depends strongly upon the orientation of the magnetic field with respect to the c axis. The magneto-resistance is probably a consequence of magneto-striction. Some information concerning the mobility of the electrons at higher temperatures (T>400°K) is derive; at lower temperatures the conduction mechanism should be rather complicated, contributions from impurity conduction being also present.