Surface magneto-optical effects in cubic antiferromagnets

Time-odd optical effects of electric quadrupole-magnetic dipole order, which are due to the spatial symmetry of a (001) surface layer, are predicted in reflection and transmission for certain classes of cubic antiferromagnet which do not exhibit bulk effects of the same multipole order. Reflection and transmission matrices for normal incidence at the vacuum-crystal interface are derived by taking the boundary conditions in relativistically covariant form, so ensuring that the requirements of reciprocity (time-reversal symmetry) are satisfied. These matrices show that the reflected and transmitted light should be rotated due to the properties of the surface layer. The possibility is discussed of observing this rotation in those classes of cubic antiferromagnet which do not display additional surface effects such as specular optical activity of surface origin or the surface Faraday effect.