Magnetic properties of Pr2/3Ca1/3MnO3/SrTiO3 multilayers

DARIO NIEBIESKIKWIAT; NESTOR HABERKORN; SILVANA GUITARRA; JULIO GUIMPEL

Karlsruhe, Germany

Conferencia; The International Conference on Magnetism 2009; 2009

Universität Karlsruhe y Forschungszentrum Karlsruhe

Ferromagnetic (FM) clusters within insulating layers of Pr2/3Ca1/3MnO3 (PCMO) are known to improve the magnetoresistance ratio of spintronic devices. Here, we study the magnetic properties of perovskite superlattices comprised of five PCMO layers of variable thickness t separated by 5nm-thick spacers of SrTiO3 (STO). Several multilayers (1.5nm¡Ât¡Â10nm) were grown on (001) STO substrates by dc magnetron sputtering. We show that the magnetization of PCMO due to the FM inclusions presents a maximum for t¡­3nm, accompanied by an abrupt increase of coercivity, exchange bias field, and Curie temperature. The nonmagnetic nature of the neighboring STO layers indicates that the observed behavior is not related to any interlayer exchange coupling, but the geometrical matching between layer thickness and FM domain size is the key driver for the enhancement of the FM moment and anisotropy energy. These results open a new door for the optimization of  erovskite based spintronic devices.