Investigation of the magnetoelectric effect in BiFeO3-BaTiO3 solid solutions

BiFeO3 forms solid solutions with BaTiO3, over the entire compositional range, with different crystal symmetries. Magnetoelectric (ME) measurements carried out with a superimposed alternating-current magnetic field, together with a time-varying direct-current magnetic field in isothermal conditions, indicated non-linearity. The peak observed coincided with a metamagnetic transition in the magnetization data. Rather than the spin flop reported earlier, it is a gradual reorientation of spins towards the field direction that destroys the spiral spin arrangement. With increasing content of BaTiO3, a quadratic signal was observed, indicating the structural dependence of the magnetoelectric effect; The temperature variation of the ME output in the investigation carried out for x = 0.75 indicates magnetic transitions.