Schottky barrier height and the ideality factor  are established for the first time in the single phase (Ga,Mn)N using a vertical geometry device. The material has been heteroepitaxially grown on commercially available low threading dislocation density GaN:Si template. The observed above 10 M resistances already at room temperature are indicative that a nearly conductive-dislocation-free electrical properties are achieved. The analysis of temperature dependence of the forward bias I-V characteristics in the frame of the thermionic emission model yields Ti-(Ga,Mn)N Schottky barrier height to be slightly lower but close in character to other metal/GaN junctions. However, the large magnitudes of the ideality factor  > 1.5 for T  300 K, point to a sizable current blocking in the structure. While it remains to be seen whether it is due to the presence of (Ga,Mn)N barrier or due to other factors which reduce the effective area of the junction, an existence of a substantial serial resistance may hold the key to explain similar observations in other devices of a corresponding structure and technological relevance.

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The combined magnetometric and microwave spectroscopy study of Fe/(Ga,Mn)As hybrids is reported. Temperature-dependent remnant magnetization data revealed unexpected non-monotonic behavior when measured along one of the in-plane crystallographic directions of (Ga,Mn)As, with a slope-sign change at the Curie point of the ferromagnetic semiconductor. Subsequent ferromagnetic resonance measurements presented uniaxial and cubic+uniaxial symmetries of in-plane magnetic anisotropy in Fe and (Ga,Mn)As, respectively. The apparent non-monotonicity of magnetization was explained as a manifestation of competition between the applied magnetic field and temperature-altered magnetic anisotropy in ferromagnetic metal layer.

Thin-lm structures composed of two kinds of ferromagnetic material metallic Fe and semiconducting (Ga,Mn)As were investigated by means of SQUID magnetometry and ferromagnetic resonance spectroscopy. Dependence of remnant magnetic moment on temperature showed unexpected anisotropic features when recorded along two orthogonal in-plane directions. For one of these orientations, the change in sign of the slope of m(T) curve at the Curie point of (Ga,Mn)As was observed, while for the other, an analogous m(T) curve retained monotonic character. Based on the comparison with ferromagnetic resonance data, the apparent non-monotonicity was attributed to the temperature-induced change of balance between the external magnetic eld and uniaxial magnetic anisotropy in the plane of Fe layer.