Magnetic interface phenomena in nano-architectures and their applications

Full text: Interfaces between heterostructure components in nanoscale films play important roles in communicating low-dimensional phenomena and act as anchor points for the direct control and tunability of device performance. In this talk I will give an overview of our group's recent investigations into the occurrence of magnetic interface phenomena in low-dimensional thin-film systems which have conceivable utility in future condensed-matter technologies. First, the magnetic interface quality of an FePt3 nano-magnet formed via ion-induced chemical disorder will be analysed. Here, neutron and electron measurements used in combination with density functional theory calculations reveal a rather counterintuitive result which could prove beneficial towards the development of ultra-high density magnetic recording devices. In a second study, the layer-averaged static magnetisation and macroscopic magneto-dynamic behaviours of a Co/Pd bilayer during hydrogen-gas cycling are analysed. To perform this characterisation, we first had to develop and commission an original sample environment which innovatively combines polarised neutron reflectometry and microwave spectroscopy. The Co/Pd interface is found to feature tailorable magnetic surface anisotropy in the presence of hydrogen gas – the mechanism of which could act as a safety switch in next-generation vehicles powered by hydrogen. (author)