Magnetic Properties of Epitaxially Grown SrRuO3 Nanodots
Using e-beam lithography of epitaxial SrRuO3 films, we succeeded in fabricating nanosized dots of SrRuO3 ranging in size from several hundred nanometers down to 15 nm. Unexpectedly, down to the smallest dot size explored, the samples were found to be magnetic. The Curie temperature depends on the size of the dots, increasing gradually from 149 K in the thin film and dots larger than 500 nm to 157 K at 30 nm dot size. Scanning transmission electron microscopy provides evidence that this behavior results from strain relaxation in the material caused by the removal of lateral constraint around the dot.
This research was done in collaboration with Hongguang Wang, Vesna Srot, and Peter A. van Aken of the StEM group.