Spin Polarized Electronic Transport in the Heusler Compound ${hbox{Pd}}_{2}{hbox{MnSn}}$

摘要

This work presents an experimental study of the magnetotransport properties in the Heusler compound ${hbox{Pd}}_{2}{hbox{MnSn}}$ . The electrical resistivity, magnetoresistance and Hall effect were measured in the temperature interval between 2 K and 350 K in the presence of magnetic fields ranging between 0 and 9 Tesla. Magnetization measurements were made as a complement to the magnetotransport experiments. Effects of spin polarized electronic currents were evidenced in the magnetotransport experiments. In particular, the spin mixing term that describes the momentum transfer between the spin dependent subbands, plays an important role in the low temperature resistivity and magnetoresistance. On the other hand, the scattering processes due to spin disorder are dominant in the intermediate and high temperatures regions. The temperature dependent Hall resistivity in ${hbox{Pd}}_{2}{hbox{MnSn}}$ shows a minimum around $T=50 {hbox{K}}$. An anomalous contribution to the Hall effect in this system was identified and discussed with basis on the k-space Berry phase theoretical predictions.