NONLINEAR SPECTROSCOPY OF ANTIFERROMAGNETIC CR2O3

Antiferromagnetic Cr2O3 is investigated by nonlinear spectroscopy. A p ronounced polarization dependence of the second harmonic spectrum was observed which is due to the interference of time-invariant and time-n oninvariant contributions to the nonlinear signal. It can be used to v isualize antiferromagnetic 180 degrees domains with high resolution in a few minutes. Both spectroscopy and topography show that in the spin -flop phase the spins are oriented in the basal plane along a twofold axis. (C) 1997 American Institute of Physics.