Writers: L. V. Costa, Maria G. Ranieri, Mario Cilense, Elson Longo, Alexandre Z. Simões
Keywords: magnetoelectric coupling; bismuth ferrite; thin films grown
Abstract: Magnetoelectric coupling was observed at room temperature in calcium modified bismuth ferrite BiFeO3 (BFO) thin films deposited on Pt/TiO2/SiO2/Si (100) substrates by the chemical solution deposition. Undoped and Ca-doped BiFeO3 films were coherently grown at a temperature of 500 °C for 2 h. The highest doped BFO film has a tetragonal structure with P4mm space group, while BFO has a rhombohedral structure with space group R3c, which can be treated as a special triclinic structure. Room temperature magnetic coercive field indicates that the undoped film is magnetically soft with maximum magnetoelectric coefficient in the longitudinal direction was about 12 V/cm. Adding Ca2+ ions to BFO in high concentration decreases the remnant polarization and stabilizes the charged domain walls which interact with oxygen vacancies reducing coercive field.
