Magnetoelectric effect inGd2CuO4

Abstract

The magnetoelectric (ME) effect is observed in the tetragonal antiferromagnet ${\mathrm{Gd}}_2$ ${\mathrm{CuO}}_4$ in magnetic fields up to 7 T. This is an observation of the ME effect in the class of tetragonal crystals with the general formula ${\mathit{R}}_2$ ${\mathrm{CuO}}_4$ (R=rare-earth), which are parent compounds for high-${\mathit{T}}_{\mathit{c}}$ superconductivity. The ME effect is shown to exist only below the ordering temperature of the rare-earth magnetic subsystem at ${\mathit{T}}_{\mathit{N}}$(Gd)=6.5 K in accordance with results based on a symmetry analysis. The field and temperature dependence of the effect confirm the magnetic structure revealed recently in this compound.