All-electrical measurements of direct spin Hall effect in GaAs with Esaki diode electrodes

摘要

We report on measurements of direct spin Hall effect in a lightly n-dopedGaAs channel. As spin detecting contacts we employed highly efficientferromagnetic Fe/(Ga,Mn)As/GaAs Esaki diode structures. We investigate bias andtemperature dependence of the measured spin Hall signal and evaluate the valueof total spin Hall conductivity and its dependence on channel conductivity andtemperature. From the results we determine skew scattering and side jumpcontribution to the total spin hall conductivity and compare it with theresults of experiments on higher conductive n-GaAs channels[Phys. Rev. Lett.105,156602(2010)]. As a result we conclude that both skewness and side jumpcontribution cannot be fully independent on the conductivity of the channel.