Quasi ballistic magnetization reversal
  We demonstrate a quasi ballistic switching of the magnetization in a microscopic mag-neto resistive memory cell. By means of time resolved magneto transport we follow the large angle precession of the free layer magnetization of a spin valve cell upon applica-tion of transverse magnetic field pulses. Stopping the field pulse after a 180 degree precession rotation leads to magnetization reversal with reversal times as short as 165 ps. This switching mode represents the fundamental ultra fast limit of field induced magnetization reversal. 
H.W. Schumacher, C. Chappert, R.C. Sousa, P.P. Freitas, J. Miltat