Magnetic anisotropy induced novel phenomena in itinerant ferromagnet SrRuO3 thin films

Complex oxides and their interfaces provide a rich platform for designing heterostructures with perpendicular magnetic anisotropy and more importantly the ability to tune such anisotropy by different strategies. SrRuO3, a unique 4d transition-metal oxide ferromagnet, is an attractive material to design novel emergent phenomena due to the strong cooperation between electron-electron correlation and spin-orbit coupling. Furthermore, the tunability of the magnetic anisotropy in SrRuO3-based heterostructures provides an opportunity to create unconventional features in the magnetic and magneto-transport properties.
This thesis focuses on studying novel features in SrRuO3 thin films and heterostructures via tuning the magnetic anisotropy of SrRuO3. We observe characteristic signatures of the Topological Hall Effect in the SrRuO3 films with multiaxial anisotropies, which are robust to magnetic field tilting and temperature variations. In addition, we observe strong uniaxial perpendicular anisotropy in SrMnO3/SrRuO3 heterostructures by adjusting the interfacial conditions. Such heterostructure system is a promising building block for practical spintronics devices where the magnetocrystalline anisotropies can be tuned and magnetization can be controlled, providing a new design strategy for memory and computing applications.
Our studies provide an important contribution to the understanding of such interfaces for future applications by exploiting the complex magnetocrystalline anisotropy, intrinsic to these materials and their manipulation by electric and spin-orbital fields.