About room temperature ferromagnetic behavior in BaTiO3 perovskite

A ferromagnetic behavior at room temperature is detected in micro-, submicro- and nano-powders of BaTiO3 perovskite by means of magnetization measurements, where the magnetic response is originated of different sources, depending on nature of the sample. For BaTiO3 micropowders is associated with the presence of a magnetic impurity, while for submicro- and nano-powders of BaTiO3 perovskite, the ferromagnetism is due to magnetic moments arising from the oxygen vacancies on the particles surface. We carry out an additional experimental confirmation of our asseverations by means of the electron paramagnetic resonance (EPR) and the low-field microwave absorption (LFMA), at X-band (8.8-9.8 GHz) and 300 K, indicating the presence of a magnetic impurity in BaTiO3 micropowders and the existence of oxygen vacancies in BaTiO3 nanopowders.