Control of magnetism at low electric fields in multiferroic 0.58BiFeO3-0.42Bi0.5K0.5TiO3 single crystal near morphotropic phase boundary

Electric field (E) control of magnetism (M) via the converse magnetoelectric (ME) effect in insulating multiferroics is promising in energy-efficient spintronic devices. However, strong ME coupling together with relatively low electric fields for E control of M is still challenging in practical applications. Here we report considerable and reproducible E control of M with E even much lower than the ferroelectric (FE) coercive field (EC) at room temperature (RT) in the multiferroic 0.58BiFeO3-0.42Bi0.5K0.5TiO3 (BF-BKT) single crystals residing in the tetragonal region, but next to the morphotropic phase boundary (MPB). The E controlled M can be substantially suppressed by high magnetic fields (H). It is revealed that the E controlled M can be rather ascribed to both the Einduced lattice distortion and phase transformation than to FE domain switching in BF-BKT. The weakened converse ME effect at high H is attributed to the H-induced suppression of phase transformation. Our results demonstrate that the converse ME effect mediated by E-sensitive lattice structures in multiferroics near MPB might be promising in achieving ultralow power spintronic devices.