We present helicity and field dependent magnetization dynamics of ferromagnetic Co/Pt multilayers, suitable for all-optical helicity-dependent switching. Employing single-shot time-resolved magneto-optical Kerr effect imaging, our study demonstrates an ultra-fast quenching of the magnetization after a single 60 fs laser pulse excitation followed by a recovery. Full demagnetization occurs within 1 ps after laser excitation. The magnetization dynamics reveals a small helicity dependence caused by magnetic circular dichroism. When an external magnetic field is applied, a heat-assisted magnetization reversal occurs on a nanosecond time scale.

Using spectroscopical magneto-optical methods, we are able to disentangle the contributions of the different layers in the net magnetization of a GdxFeCo/SiN/GdyFeCo heterostructure. By static magneto-optical measurements, time-resolved magneto-optical Kerr effect spectroscopy and temperature and laser fluence dependence study of the magnetization dynamics, we study the laser-induced magnetization dynamics and reversal in this multilayer system for each layer separately.

We report handedness-sensitive surface plasmon polariton (SPP) emission in mirror-symmetric ensembles of elliptical nanoholes made in a thin gold film. It is found by means of rigorous calculations and scanning near-field optical microscopy that SPP excitation direction depends on the direction of circularly polarized illumination E-vector rotation. An analytical model based on anisotropic polarizability of each nanohole is presented. Both the experimental and calculated results are in agreement with Curie's principle, and contribute to better understanding of symmetry in plasmonics.

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