2015 CAP Congress / Congrès de l'ACP 2015

Controlling magnetization dynamics with artificial pinning sites in thin magnetic disks

17 Jun 2015, 14:15

15m

NINT Taylor room (University of Alberta)

Oral (Student, In Competition) / Orale (Étudiant(e), inscrit à la compétition) Condensed Matter and Materials Physics / Physique de la matière condensée et matériaux (DCMMP-DPMCM) W2-1 Spintronics and spintronic devices (DCMMP) / Spintronique et technologies spintroniques (DPMCM)

Speaker

Fatemeh Fani Sani (UofA)

Description

Spatial inhomogeneity on the nanoscale is intrinsic to most thin film materials used in nanomagnetic technology, and can affect both static and dynamic magnetic responses [1]. Understanding the detailed effects of local inhomogeneity becomes increasingly important as device dimensions shrink. Focused ion beam irradiation is an elegant way to carry out local magnetic patterning to create highly confined magnetic pinning sites. The strength and lateral dimension of the sites are tailored by varying the beam dose. A quantitative understanding of magnetic pinning has been gained through studies of the quasi-static (Barkhausen) response of a magnetic vortex core interacting with the local energetic landscape [2,3]. The corresponding modification of dynamics arising from the presence of engineered pinning sites will be discussed. Experimental measurements using an extension of nanomechanical torque magnetometry [4], are complemented by numerical micromagnetic simulations. Refs: 1- R. L. Compton et al., PRL 97, 137202 (2006). 2- F. Fani Sani , et al., J. Appl. Phys. 115 , 17D131 (2014). 3- J.A.J. Burgess et al., Science 339 , 1051 (2013). 4- J.E. Losby, et al., Solid State Commun. (2014)