**4. Conclusions**

In this work, the combination of anisotropy and exchange striction in DyFeO3 provides a guiding principle for designing high-sensitivity spin-driven multiferroicity. Especially in the *ab* plane, the direction of the magnetic anisotropy (or the anisotropy energy) of the Dy3+ ions can be modulated by a smaller magnetic field, which alters the exchange striction and leads to a Δ*P*<sup>c</sup> sensitive to the external magnetic field. That is, the combination of the magnetic anisotropy of the Dy3+ spin and the exchange striction between the Fe3+ and Dy3+ spins leads to the Δ*Pc*. The Δ*Pc* exhibits high magnetic-field sensitivity. This work deepens

the understanding of the effects of the multiple magnetic orders on the magnetoelectric coupling of multiferroic DyFeO3 and will be beneficial in searching for novel multiferroic material systems with high magnetic-field sensitivity.

**Supplementary Materials:** The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/nano12183092/s1, Table S1: The lattice parameters of the DyFeO3 single crystal; Figure S1: The measurement schematic of the electric polarization (*Pc*) under pulsed magnetic fields; Figure S2: Magnetic phase diagrams determined with the magnetization and polarization measurements.

**Author Contributions:** Z.Z. and X.H. contributed equally to this work. Writing—original draft preparation, Z.Z. and X.H.; supervision, Y.S., H.N. and M.W.; investigation, D.J., X.Z., Y.L., H.H. and Z.O.; writing—review and editing, Z.C. and Z.X. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the National Natural Science Foundation of China (Grant Nos. 11674115, 51861135104, and 21875249). Z.C. thanks the Australian Research Council (Grant No. DP190100150) for support.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
