BiFeO₃ has been recognized as one of the most important room-temperature single-phase multiferroic materials, but it still suffers from several drawbacks especially the weak magnetoelectric coupling. In the present work, the electric-field-controlled magnetism is achieved in Bi_1-xGd_xFeO₃ system, which involves a field-induced transition of Pna2₁/R3c at the morphotropic phase boundary region, and the magnetic state is switched between cycloidal state and canted antiferromagnetic state. The electric-field-controlled magnetism becomes reversible with the help of annealing, which is confirmed by magnetic hysteresis loops and the quantitative ratio of the involved phases for the as-sintered, as-poled and as-annealed samples. Compared with the systems of Bi_1-xNd_xFeO₃ and Bi_1-xSm_xFeO₃, it is easier to tune the symmetry from R3c to Pna2₁ with lower rare earth-content, and the field-induced transition is more apparent and subsequently leads to more significant electric-field-controlled magnetism in a wider composition range.

BiFeO ₃已被公认为最重要的室温单相多铁性材料之一，但它仍然存在一些缺点，尤其是弱磁电耦合。在目前的工作中，电场控制的磁性是在 Bi _1-x Gd _x FeO ₃系统中实现的，它涉及Pna 2 ₁ / R 3 c的场诱导跃迁在同向相边界区域，磁态在摆线态和倾斜的反铁磁态之间切换。电场控制的磁性在退火的帮助下变得可逆，这通过磁滞回线和烧结、极化和退火样品的相关相的定量比得到证实。与Bi _1-x Nd _x FeO ₃和Bi _1-x Sm _x FeO _{3 系统相比}，更容易将对称性从R 3 c 调整到Pna 2 ₁ 稀土含量较低，场致转变更明显，随后在更宽的成分范围内导致更显着的电场控制磁性。