Chirality-induced asymmetric magnetic nucleation in Pt/Co/AlOx ultrathin   microstructures
  The nucleation of reversed magnetic domains in Pt/Co/AlO$_{x}$ microstructures with perpendicular anisotropy was studied experimentally in the presence of an in-plane magnetic field. For large enough in-plane field, nucleation was observed preferentially at an edge of the sample normal to this field. The position at which nucleation takes place was observed to depend in a chiral way on the initial magnetization and applied field directions. An explanation of these results is proposed, based on the existence of a sizable Dzyaloshinskii-Moriya interaction in this sample. Another consequence of this interaction is that the energy of domain walls can become negative for in-plane fields smaller than the effective anisotropy field. 
Stefania Pizzini (NEEL), Jan Vogel (NEEL), Stanislas Rohart (LPS),   Liliana-Daniela Buda (SPINTEC - UMR 8191), E. Ju\'e (SP...
cond-mat.mtrl-sci