Electrical Measurement of the Direct Spin Hall Effect in Fe/In_xGa_(1-x)As Heterostructures

We report on an all-electrical measurement of the spin Hall effect in epitaxial Fe/In_{x}Ga_{1-x}As heterostructures with n-type channel doping (Si) and highly doped Schottky tunnel barriers. A transverse spin current generated by an ordinary charge current flowing in the In_{x}Ga_{1-x}As is detected by measuring the spin accumulation at the edges of the channel. The spin accumulation is identified through the observation of a Hanle effect in the Hall voltage measured by pairs of ferromagnetic contacts. We investigate the bias and temperature dependence of the resulting Hanle signal and determine the skew and side-jump contributions to the total spin Hall conductivity.