Aa. Mukhin et al., GYROTROPIC PROPERTIES OF ANTIFERROMAGNETS NEAR AFMR - SUBMILLIMETER QUASI-OPTICAL SPECTROSCOPY OF YFEO3 AND CR2O3, Journal of magnetism and magnetic materials, 183(1-2), 1998, pp. 157-159
Magnetic gyrotropy effects near antiferromagnetic resonance (AFMR) det
ermined by weak ferromagnetism (YFeO3) and magnetoelectric effect (Cr2
O3) have been studied using quasi-optical submillimeter backward-wave-
oscillator technique in the frequency range 3.2-13 cm(-1). A noticeabl
e rotation of an optical indicatrix and increase of an ellipticity hav
e been revealed near AFMR in both antiferromagnets, which present a ma
nifestation of a Faraday rotation in YFeO3 and gyrotropic birefringenc
e in Cr2O3. Theoretical calculations and computer simulations made it
possible to describe the observed spectral taking into account the res
onance behaviour of magnetic, magnetoelectric and electric susceptibil
ities, and to determine corresponding parameters, in particular, an AF
MR mode contribution to the static magnetic and magnetoelectric suscep
tibilities. (C) 1998 Elsevier Science B.V. All rights reserved.