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Summary form only given. Hybrid recording has already been realized in laser beam assisted perpendicular magnetic recording in audio recordable MiniDiscs. In the year 2000 alone, more than 20 million drives and 220 million disks were shipped. Hybrid recording is expected to be a very strong candidate in the near future in the very high density region, exceeding terabits/in/sup 2/. Here, we report on hybrid recording with the capability to overcome two of the main serious problems; the paramagnetic limit in high density region and the writing speed limit caused by ferromagnetic resonance around 2 to 5 GHz.

Summary form only given. The understanding of coherent switching of a magnetic thin film system is required for practical applications such as the future MRAM memory cell. The Landau-Lifshitz dynamics describing the precessional motion of the magnetic spin system is studied by excitation of lithographically structured micron-sized Permalloy elements by ultra-short magnetic field pulses. The shortest time needed for the reversal of the magnetisation is given by the half of one full precessional oscillation but for this a complete suppression of the magnetisation ringing after the switching process is needed. This requires stopping of the precessional motion at exactly this time, which in practice means stopping this motion on a time scale much shorter than the typical damping time. We will present a technique that enables us to arbitrarily control the magnetisation precession on a picosecond timescale. The method is based on two independently triggered GaAs photoswitches, excited by femtosecond laserpulses. The femtosecond-laserpulse-system allows us to measure the in-plane components of the magnetisation by means of magnetisation induced second harmonic generation (MSHG) while the polar component is probed by linear MOKE.