Magnetic field-induced polarization reversal in Y-type hexaferrites Ba0.7 Sr1.3CoZnFe11AlO22 single crystals

Abstract Y-type hexaferrites with non-collinear conical magnetic structures, which induce electric polarization (P), are prospective single-phase multiferroics with broad applications, such as magnetic sensors, energy convertors, and memory devices, among others. Y-type hexaferrites have attracted considerable attention. In this study, we investigated the magnetoelectric properties of Ba0.7Sr1.3CoZnFe11AlO22 single crystals with Y-type hexaferrite structures by replacing half of Zn2+ ions with Co2+ ions. A transition from a screw order to the ferromagnetic is observed at TN2 = 356 K in Ba0.7Sr1.3CoZnFe11AlO22 single crystals. The electric polarization (P) and magnetoelectric coupling coefficient ( α ) reach a maximum of 130 μC/m2 and 16667 ps/m at T = 30 K and E = 880 kV/m, respectively. Most importantly, the in-plane Hab induced P can be fully reversed by applying in-plane Hab and it maintains a non-zero value even when the applied magnetic field is zero. Since the P does not decay and repeats many times under a fluctuating low magnetic field, it is important for potential applications in new types of non-volatile memory devices.