Current-driven domain wall motion along ferromagnetic strips with periodically-modulated perpendicular anisotropy

[EN]The dynamics of magnetic domain walls along ferromagnetic strips with spatially modulated perpendicular magnetic anisotropy are theoretically studied by means of micromagnetic simulations. Ferromagnetic layers with a periodic sawtooth profile of the anisotropy depict a well-defined set of energy...

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Detalles Bibliográficos
Autores: Sánchez-Tejerina, Luis, Alejos Ducal, Óscar, Raposo Funcia, Víctor Javier, Martínez Vecino, Eduardo
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/138239
Acceso en línea:http://hdl.handle.net/10366/138239
Access Level:acceso abierto
Palabra clave:Magnetism
Domain wall
Computational physics
Spin-orbit torque
Magnetic memory
Descripción
Sumario:[EN]The dynamics of magnetic domain walls along ferromagnetic strips with spatially modulated perpendicular magnetic anisotropy are theoretically studied by means of micromagnetic simulations. Ferromagnetic layers with a periodic sawtooth profile of the anisotropy depict a well-defined set of energy minima where the walls are pinned in the absence of external stimuli, and favor the unidirectional propagation of domain walls. The performance of the current-driven domain wall motion along these ratchet-like systems is compared to the field-driven case. Our study indicates that the current-driven domain wall motion exhibits significant improvements with respect to the field-driven case in terms of bit shifting speed and storage density, and therefore, it is suggested for the development of novel devices. The feasibility of these current-driven ratchet devices is studied by means of realistic micromagnetic simulations and supported by a one-dimensional model updated to take into account the periodic sawthooth anisotropy profile. Finally, the current-driven domain wall motion is also evaluated in systems with a triangular modulation of the anisotropy designed to promote the bidirectional shifting of a series of walls, a functionality that cannot be achieved by magnetic fields.