Magnetoelectric measurements on and

Abstract

and are members of the Aurivillius family of compounds having simultaneous electrical and magnetic ordering. Magnetoelectric measurements carried out in a linear time-varying magnetic field with an alternating-current field superimposed yielded a non-linear signal. The shift from linearity, which is not usually observed for antiferromagnetic materials, may be due the tilt in the octahedra. The variation of the magnetoelectric output with temperature for and indicated magnetic anomalies with enhanced sensitivity, corresponding to those in magnetization data.