Ferromagnetic GaMnAs containing up to 10% Mn has been grown by migration-enhanced epitaxy at a substrate temperature of 150 °C. The lattice constant of hypothetical zinc-blende structure MnAs is determined to be 5.90 Å, which deviates somewhat from previously reported values. This deviation is ascribed to growth-condition-dependent density of point defects. Magnetization measurements showed an onset of ferromagnetic ordering around 75 K for the GaMnAs layer with 10% Mn. This means that the trend of falling Curie temperatures with increasing Mn concentrations above 5.3% is broken.

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We present x-ray diffraction studies of a CdSe distribution profile along the growth direction in CdSe/ZnSe submonolayer superlattices (SLs) grown by molecular beam epitaxy. The performed theoretical simulations show that the shape of both (004)- and (002)-reflection rocking curves is very sensitive to the vertical CdSe distribution around the intended deposition yplanes. In particular, broadening of the CdSe submonolayer insertions results in a decrease in SL (±1) and (±2) satellite intensities. Comparison of the simulations and experimental data allows us to conclude that CdSe sheets in the as-grown SL samples are asymmetrically broaden up to 5 monolayers.

Contact resistance between interlaced conductive yarns will under certain circumstances constitute a problem for sensor applications and electrical routing in interactive textile structures. This type of resistance could alter the effective area of the sensor and introduce hot-spots in the routing. This paper presents a technique for measuring contact resistances on fabric samples. The samples used are unit cells of plain weave, that is, two conductive (silver-coated) yarns in the warp direction and two in the weft direction. The numerical values for the contact resistance are of the order of Rc ≈ 0.3 Ω. A resistor network made of through-hole film resistors with known values is used for evaluation of the method. The results show that the technique provides values typically within ±1% error compared with the known resistor values. Thus, the method can be used in order to calculate the contact resistances of a woven conductive textile.

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