Electric polarization induced by low magnetic field in the W-type hexaferrite BaCoFe17O27 single crystal

Recently, the noncollinear magnetic structure with varying Co/Zn ratios was reported in the W-type hexaferrites using neutron powder diffraction. It is believed that these noncollinear spin orderings may stimulate magnetoelectric (ME) effect in the W-type hexaferrite. Herein, we present distinct evidence of ME response through systematic investigation on the magnetic and ferroelectric properties in BaCoFe17O27. Magnetization exhibits two different anomalies at TC1 ∼ 350 K and TC2 ∼ 150 K, indicating the formation of long-range longitudinal spin configurations and the spin reorientation transition, respectively. We have found that the low field-driven electric polarization has been observed under the ME poling condition of E ⊥ (H ⊥ c, and c). Spin current mechanism is mainly considered as the physics origin in its ME response, corresponding to the other hexaferrites as reported early. In addition, the weak electric polarization observed with E(⊥c)//H(⊥c) suggests that the p–d hybridization mechanism should also be contributed to the ME response in this compound. Therefore, BaCoFe17O27 presents an intrinsic magnetoelectric effect and provides a thought for people to seek and study the more single-phase ME compounds from the viewpoint of foundational and applications.