Magnetoelectric Interaction In Crystals Observed By Nonlinear Magneto-Optics
Published 2004 · Materials Science
Optical second harmonic generation was employed to investigate linear and higher-order magnetoelectric (ME) effects in magnetic oxides. The characteristic degrees of freedom of optical experiments reveal aspects of ME behavior which are not accessible by alternative techniques. ME 180° domains have been observed in Cr2O3 in the absence and presence of a magnetic field. Their transformation properties were used to determine the magnetic structure in the spinflop phase. A hidden magnetic phase transition was identified in the hexagonal rare-earth manganites which is triggered by a linear ME interaction rooting microscopically in 3d - 4f superexchange. Higher-order ME interactions lead to a clamping of antiferromagnetic to ferroelectric domain walls in YMnO3.