Magnetic Information in the Light Diffracted by Submicron-scale Periodic Magnetic Arrays

The experimental and theoretical aspects for obtaining the magnetic information carried by laser beams diffracted from an array of nano-sized magnetic objects is reviewed. Experimentally it will be shown that the Magneto Optic Kerr Effect (MOKE) hysteresis loops recorded on diffracted beams can be quite different from those recorded in the reflected beam. We will show that the Diffracted MOKE (D-MOKE) loops are proportional to the magnetic form factor, or equivalently, to the Fourier component of the magnetization corresponding to the reciprocal lattice vector of the diffracted beam. In conjunction with micromagnetic simulations D-MOKE provides a powerful and non-destructive technique for investigating the magnetization reversal process in submicron sized magnetic particles.