Magnetoelectric coupling effect in transition metal modified polycrystalline BiFeO3 thin films

• Transition metal modified polycrystalline BiFeO3 thin films prepared using PLD.
• High ME-coupling response was observed in co-substituted BiFeO3 thin films.
• High magnetization ~35 emu/cm3 at a maximum field of H ~20 kOe.
• Low leakage current might be due to co-substitution in BiFeO3 thin films.
• A notable piezoelectric constant d33 ~94 pm/V was found in BiFeO3 thin films.

Rare-earth (Sm) and transition metal (Co) modified polycrystalline BiFeO3 (BFO) thin films have been deposited on Pt/TiO2/SiO2/Si substrate successfully through pulsed laser deposition (PLD) technique. Piezoelectric, leakage current and temperature dependent dielectric and magnetic behaviour were investigated for the films. Typical “butterfly-shaped” loop were observed in BSFCO films with an effective piezoelectric constant (d33) ~94 pm/V at 0.6 MV/cm. High dielectric constant ~900 and low dielectric loss ~0.25 were observed at room temperature. M–H loops have shown relatively high saturation magnetization ~35 emu/cm3 at a maximum field of H ~20 kOe. Enhanced magnetoelectric coupling response is observed under applied magnetic field. The multiferroic, piezoelectric, leakage current behaviours were explored. Such studies should be helpful in designing multiferroic materials based on BSFCO films.