Analysis of magneto-elastic coupling mechanisms in FePt/BaTiO3 bilayers through structural and magnetic characterization

A. ROMÁN, A. LÓPEZ PEDROSO, L. NEÑER, D. PEREZ, M. AGUIRRE, M. SOARES, M. SIRENA, A. BUTERA, L. STEREN

Conferencia; 9th Joint European Magnetic Symposia; 2018

The design and fabrication of multiferroics (MF) is one of the main challenges for the development of oxide spintronics. Tuning the magnetic state by electric field or strains appears to be the key forlow-energy devices. Magneto-electric and magneto-elastic coupling at interfaces between ferromagnetic (FM) andferroelectric (FE) layers are at the origin of these phenomena [1]. FePt/BaTiO3 seems to be a very promising system. First-principle calculations revealed recently that important changes of magnetic anisotropy should be observed on the FePt layer when BaTiO3(BTO) is poled [2]. Moreover, BTO piezoelectric and FePt magnetostrictive properties make FePt/BTO heterostructure a highly tunable multiferoic. To study coupling mechanisms in the FePt/BTO structures, we grew a series of FePt/BTO bilayers by sputtering onto (001) SrTiO3 substrates. The characterization of the magnetic anisotropy of the samples was performed by magnetization measurements, while the domain structure was oberved by magnetic force microscopy. The crystalline structure of each constituents was investigated by X-ray Diffraction using synchrotron radiation at LNLS. , measured in different geometries and temperatures. These experiments were performed at the LNLS, Campinas-Brazil.The study of the crystalline structure of the bilayer, in correlation to magnetic properties studies served us to get a deep insight into the magneto-elastic coupling mechanisms in this system.[1] C. A. Vaz, J. Phys: Condens. Matter, 24, 333201(2012)[2] M. Lee et al, J. Appl. Phys., 113, 17C729 (2013)