Temperature dependence of the intrinsic Faraday rotation of ErFeO3

The Faraday rotation of ErFeO₃ as a function of temperature was measured from ambient down to the spin reorientation region (90 to 100°K) at a wavelength of 6070 Å. The intrinsic Faraday rotation increases gradually with decreasing temperature and then drops rapidly to zero in the spin reorientation region. It is concluded that the contribution of the polarized Er³⁺ magnetic moments to the measured rotation is negligible and that the Faraday effect is due almost entirely to the magnetic moments of the Fe³⁺ ions.