Magnetic-field-induced toroidal moment in the magnetoelectric Cr2O3

The appearance of a toroidal moment is observed in the magnetoelectric Cr2O 3 in a strong magnetic field above the spin-flop transition field. This con clusion is based on the experimentally established fact that the off-diagon al components of the magnetoelectric susceptibility tensor of Cr2O3 contain s an antisymmetric part that is dual to the toroidal moment. Therefore it h as been shown that the magnetoelectric Cr2O3 in the spin-flop phase can be classified as a toroic. (C) 1999 American Institute of Physics. [S0021-3640 (99)00904-4].