Anisotropy of the Faraday rotation of CoFe2O4 single crystals

Abstract

Faraday rotation measurements, performed at 1150 nm wavelength on single‐crystal platelets of CoFe₂O₄ with two different crystallographic orientations [100] and [111], are presented under magnetic fields up to 20 kOe, in the 5–580‐K temperature range. A high anisotropy of magnetic origin is observed particularly at low temperatures (T<230 K) where saturation cannot be obtained along the [111] direction in a 20‐kOe magnetic field. The high Faraday rotation measured at 1150 nm and 300 K (−5700°/cm) is about twice that of Bi‐substituted garnet films at this wavelength. The results are interpreted on the basis of contributions proportional to the magnetization of each magnetic sublattice.