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Heat assisted magnetic recording (HAMR) requires a sufficiently small heat spot, which is much below the diffraction limit of the wavelength of the used light. This can be achieved with an optical near field source consisting of a small metallic wedge which supports edge plasmons. The power transfer between a dielectric rectangular waveguide and this metallic wedge is investigated in simulations and experiments. Beating of two eigenmodes of this system leads to power oscillations between the waveguide core and the edge plasmon along their overlap length. This was confirmed in near field experiments which are based on the evaporation of phase change material with the absorbed optical near fields as heat source. Devices with weak and strong edge plasmon excitation could be clearly distinguished in a simple far field experiment.

RF vortex spin-transfer oscillators based on low RA magnetic tunnel junctions were investigated. A very high power of excitations has been obtained characterized by a power spectral density containing a very sharp peak at the fundamental frequency and a series of harmonics. The observed behaviour is attributed to the combined effect of Oersted-Ampere field generated by the large applied dc-current and of the spin transfer torque. We furthermore show the synchronization of a vortex oscillation by applying a RF bias microwave which frequency is twice the oscillator fundamental frequency.