Vortex core switching by coherent excitation with single in-plane   magnetic field pulses
  The bistability of the core magnetization of nano-scaled magnets with a magnetic vortex configuration has great potential for data storage applications. To exploit this, reliable switching between the two possible states is needed. Time resolved x-ray microscopy was used to study the response of the vortex core to excitation pulses at sub-ns timescales and image the vortex core switching. A reliable switching process by coherent excitation with leading and trailing edges of in-plane magnetic field pulses was found and compared with micromagnetic simulations. 
Markus Weigand, Bartel Van Waeyenberge, Arne Vansteenkiste, Michael   Curcic, Vitalij Sackmann, Hermann Stoll, Tolek Tyliszc...