Fig. 1. (Colour online) Arrott plots at different temperatures for a 300 nm-wide Hall bar of (Ga,Mn)As. The inset shows a close-up view of the Arrott plots near the ferromagnetic transition, which confirms that T_C is slightly above 200 K. (Adapted from Ref. [15])

Fig. 2. (Colour online) Gate-voltage dependence of (a) magnetic anisotropy fields H_ani and (b) Gilbert damping constant α. (c) Damping constant α (closed symbols) and ratio of the superparamagnetic-like component M_SP to the total magnetic component M_tot (open symbols) as a function of resistivity ρ. Circles (triangles) are for the sample with x = 0.075 (0.068), whose ρ is changed by annealing. Squares are for the MIS structure, whose ρ is changed by applied gate voltage. (Adapted from Ref. [30])

Fig. 3. (Colour online) (a) Ferromagnetic resonance and (b) DC voltage V spectrum obtained at temperature T = 45 K and magnetic field angle θ_H = 90° for (Ga,Mn)As/un-doped GaAs. Magnetic field angle θ_H dependence of (c) symmetric component V_sym and (d) anti-symmetric component V_a-sym of the DC voltage, normalized by the microwave absorption coefficient I, which can be well fitted by the planar Hall effect and the anomalous Hall effect of (Ga,Mn)As. (Adapted from Ref. [37])

Fig. 4. (Colour online) The magnetic-field angle θ_H dependence of (a) the FMR resonant field H_R and (b) the linewidth ΔH for (Ga,Mn)As/p-GaAs and (Ga,Mn)As/undoped GaAs. The resonance fields for both samples are identical, while a larger linewidth is found for (Ga,Mn)As/p-GaAs, indicating the existence of spin pumping. (Adapted from Ref. [37])

Fig. 5. (Colour online) Angular dependence of the DC voltage for (Ga,Mn)As/p-GaAs.Magnetic field angle θ_H dependence of (a) symmetric component V_sym and (b) anti-symmetric component V_a-sym of the DC voltage, normalized by the microwave absorption coefficient I. Dotted and dashed lines in (a) show the θ_H dependence of the DC voltages induced by the inverse spin Hall effect V_ISHE/I and planar Hall effect V_PHE/I, where the ratio of the magnitudes of V_ISHE and V_PHE is adjusted to reproduce the experimental result. Solid line represents total contributions, V_ISHE/I + V_PHE/I. Solid line in (b) shows the θ_H dependence of the DC voltage induced by the anomalous Hall effect V_AHE normalized by I. (Adapted from Ref. [37])

Fig. 6. (Colour online) Experimentally determined magnitude and direction of the in-plane spin-orbit fields, which are normalized by a unit current density of 10¹¹ A/m².

Fig. 7. (Colour online) Polar plot of in-plane spin-orbit fields under different gate-voltages. The arrows represent direction and relative strength of h_eff, and the solid lines represent the spin-orbit energy splitting. (Adapted from Ref. [62])

Fig. 8. (Colour online) Magnetic-field angle φ_H dependence of the damping constant α for Fe thickness of (a) 1.9 nm and (b) 1.3 nm. Isotropic damping is observed for 1.9 nm-Fe. However, for Fe thickness of 1.3 nm, a larger α along <110> is observed, and α gradually decreases until approaching . The anisotropic damping shows 2-fold symmetry, which results from the anisotropic density of states at the Fe/GaAs interface, as shown by open symbols in (b). (Adapted from Ref. [66])