This paper reports on the growth of Cr-doped GaN layers by metal organic vapor phase epitaxy (MOVPE) and their characterization for possible spintronic applications. We have used bis (cyclopentadienyl)chromium (Cp 2 Cr) to intentionally incorporate chromium (Cr) during GaN layer growth. The effects of the carrier gas, hardware setup, and growth temperature on the growth of Cr-doped GaN were investigated. A linear dependence between mole fraction of Cp 2 Cr in the gas phase and incorporated Cr in the solid phase was found. The surface morphology was mostly influenced by carrier gas and growth temperature. A remanent magnetization was observed even above room temperature.

The phase transformation of NdFeB melt-spun alloys with low Nd content of 4–8 at. % was investigated by thermomagnetic analysis and x-ray diffractometry. Experimental results have shown that the metastable Nd2Fe23B3 compound formed in the alloys is considered to be transformed to Nd2Fe23B3+α-Fe+Fe3B in the temperature range of 550–690 °C, α-Fe+Fe3B+Nd1+eFe4B4 in the temperature range of 690–730 °C and finally α-Fe+Nd1+eFe4B4 above 840 °C. From the results, it has been concluded that Nd2Fe14B is not formed from metastable Nd2Fe23B3. On the other hand, the melt-spun alloy of Nd2Fe23B3 (∼Nd7.1Fe82.1B10.7) annealed under optimum conditions has been found to be composed of α-Fe, Fe3B, and Nd2Fe14B phases. The alloy has a coercivity comparable to Fe3B-based Nd4Fe77B19 and relatively high-energy product of about 71.6 kJ/m3 (∼9 MG Oe).