AlN/Fe/AlN/Cu nanostructures with ultrathin Fe grown by sputtering on Si substrates are evaluated as probes for magnetooptical (MO) mapping of weak currents. They are considered for a laser wavelength of lambda = 410 nm (3.02 eV) and operate at oblique light incidence angles, phi((0)), to enable detection of both in-plane and out-of-plane magnetization.
Their performance is evaluated in terms of MO reflected wave electric field amplitudes. The maximal MO amplitudes in AlN/Fe/AlN/Cu are achieved by a proper choice of layer thicknesses.
The nanostructures were characterized by MO polar Kerr effect at phi((0)) approximate to 5 degrees and longitudinal Kerr effect spectra (phi((0)) = 45 degrees) at photon energies between 1 and 5 eV. The nominal profiles were refined using a model-based analysis of the spectra.
Closed form analytical expressions are provided, which are useful in the search for maximal MO amplitudes. (C) 2014 AIP Publishing LLC.