Magnetic-Field-Induced Ferroelectric State in DyFeO3

Versatile and gigantic magnetoelectric (ME) phenomena have been found for a single crystal of ${mathrm{DyFeO}}_{3}$. Below the antiferromagnetic ordering temperature of Dy moments, a linear-ME tensor component as large as ${ensuremath{alpha}}_{zz}ensuremath{sim}2.4ifmmodetimeselsetexttimesfi{}{10}^{ensuremath{-}2}text{ }text{ }mathrm{esu}$ is observed. It is also revealed that application of magnetic field along the $c$ axis induces a multiferroic (weakly ferromagnetic and ferroelectric) phase with magnetization [$ensuremath{ge}0.5{ensuremath{mu}}_{B}/mathrm{text{formula unit}}$ (f.u.)] and electric polarization ($ensuremath{ge}0.2text{ }text{ }ensuremath{mu}mathrm{C}/text{ }text{ }{mathrm{cm}}^{2}$) both along the $c$ axis. Exchange striction working between adjacent ${mathrm{Fe}}^{3+}$ and ${mathrm{Dy}}^{3+}$ layers with the respective layered antiferromagnetic components is proposed as the origin of the ferroelectric polarization in the multiferroic phase.