During my secondment at Seagate, I focused my work on two topics: (a) the research on strong ferromagnets with high damping and (b) the study of metal-waveguide interfaces for plasmonic application. For both topics, I employed ab initio calculations based on Density Functional Theory.
(a) We studied all the possible combinations of the strong ferromagnet FeCo doped with 4d and 5d elements. The results show an increase of the damping parameter by a factor of 5-7 by doping FeCo with some of these elements at low concentration at the expense of a reduction of the total magnetization. Increased damping parameter was attributed to the large spin orbit coupling present in the 5d elements. This work was done in collaboration with Rudra Banerjee.
(b) We studied the gold interfaces with other elements in order to produce a plasmonic heterostructure thermally stable above 800 Kelvin. This preliminary study was restricted to elements with good lattice matching with gold and retaining the same face centered cubic symmetry. Initial exploration of some alternative materials for the plasmonic application was also carried out. This work was done in collaboration with Raquel Esteban Puyuelo.