Speaker
Description
Hybrid material systems combining semiconductors and magnetic nanostructures are prospective building-blocks for the next generation of high-density recording media. In phase-separated (Ga$\delta$FeN) layers grown epitaxially on Al$_{x}$Ga$_{1-x}$N buffers, the specific concentration of Al determines the density of strain-related dislocations, which allow controlling the preferential formation of either $\varepsilon$-Fe$_{3}$N or $\gamma$’-Ga$_{y}$Fe$_{4-y}$N nanocrystals.
In this work, the influence of an AlN stopping barrier on the structural properties of Ga$\delta$FeN / Al$_{0.1}$Ga$_{0.9}$N heterostructures is systematically studied via transmission electron microscopy. Through the addition of the AlN stopping barrier, the strain-related dislocations in the buffer layer can be adjusted to stabilise the specific nanocrystal phases that determine the magnetic properties of the system.
