Nondestructive ultrafast steering of a magnetic vortex by terahertz pulses.

Electric control of magnetic vortex dynamics in a reproducible way on an ultrafast time scale is a key element in the quest for efficient spintronic devices with low-energy consumption. To be useful, the control scheme should ideally be swift, be scalable, be noninvasive, and result in reliable magnetic switching. Such requirements, particularly the reproducibility of altering the vortex chirality and/or polarity, are not yet met by magnetic vortex switching via external magnetic fields, spin-polarized currents, spin waves, or laser pulses. Here, we demonstrate a novel packaged-skyrmion-mediated vortex switching process driven by a simple sequence of picosecond electrical field pulses via magnetoelectric interactions. Both the vortex chirality and polarity show a well-defined reversal behavior. The unambiguous repeated switching between four different magnetic vortex states provides an energy-efficient, highly localized, and coherent control method for nonvolatile magnetic vortex-based information storage and handling. Magnetic nanomaterials: Ultrafast vortex control for energy saving spintronics Researchers in China and Germany demonstrated a simple method for controlling magnetic patterns that are useful for data storage and information processing. Magnetic nanostructures are engineered as to host swirling magnetic vortices. The vortex intrinsic properties such as the voretx sense of rotations or polarity are well defined and thus are predestinate as digital information carriers. Furthermore, the magnetic nanostructures are readily integrated in existing computers. Chenglong Jia from Lanzhou University, Jamal Berakdar from Martin-Luther Universität Halle-Wittenberg and their co-workers demonstrated how to process the so stored information swiftly by switching both the vortex's sense of rotation and the orientation of its magnetic field using at a simple sequence of ultra-short, low average-energy electric-field pulses. The team believe that their method is scalable, non-invasive, reliable and reversible, fullfing thus important prerequisites for practical implementation. Non-destructive ultrafast control of magnetic vortices by a simple sequence of time asymmetric electric-field pulses. [ABSTRACT FROM AUTHOR]