Magneto-optical properties and the potential application of GaAs with magnetic MnAs nanoclusters

Abstract
The giant magneto-optical effect of ferromagnetic MnAs nanoclusters embedded in GaAs is shown. The Faraday rotation angle at 0.98 μm reaches about 0.2°/μm at 2000 Oe. The potential of this magneto-optical material for use as a Faraday rotator operating at 0.98 μm is demonstrated by the Verdet constant of the film which is 16 times larger than that of (Cd,Mn,Hg)Te commercially developed for an optical isolator. The fabrication of this material is compatible with that of semiconductor-based devices.