ELFT HÍRADÓ

[Szeminárium koordinátor <sem-admin AT szfki.hu>]

SZFI SeminarElena VedmedenkoUniversity of Hamburg (host: Rózsa Levente)Recent 
progress in studies of interlayer Dzyaloshinskii-Moriya interactionsTuesday, 
24 September 2024, 10:00, KFKI Campus, Bldg. 1, 2nd floor, Conference RoomIn 
this talk, an overview of recent progress in the study of the interlayer 
Dzyaloshinskii-Moriya interaction (IL-DMI) will be presented. This interlayer 
DMI induces a unique chirality of magnetization not only within a layer 
plane, as the interfacial (IF)-DMI does, but also across the multilayers 
[1,2] and its strength can be comparable to that of the IF-DMI (0.1-0.2 
mJ/m2). In particular, it will be shown that IL-DMI can occur not only in 
layered heavy metal/ferromagnet interfaces, but also in multilayers with 
spacers made of rather light metals. An example of such a system give 
Co/Ag/Co trilayers, which were recently studied with the aid of 
surface-sensitive magneto-optical measurements that take advantage of the 
light penetration depth [3] and confirmed by first-principle calculations 
[4]. It will be also shown that symmetry of interfacial and interlayer 
exchange interactions is different, although they both arise from pairwise 
exchange interactions between magnetic sites mediated by nonmagnetic atoms. 
Unlike IF-DMI, which does not contribute to the FMR frequencies, IL-DMI 
alters the frequencies of fundamental FMR modes and can be separated from 
other contributions by an FMR experiment. It will also be shown how the 
IL-DMI changes the magnetic order within the magnetic planes [5]. The 
combination of the described phenomena opens up new avenues for the design of 
three-dimensional chiral spin structures combining IF- and IL-DMI and paves 
the way for enhancements of the DMI strength.  [1] E. Y. Vedmedenko, P. 
Riego, J. A. Arregi and A. Berger (2019), Phys. Rev. Lett. 122, 257202. [2] 
A. Fernandez-Pacheco, E. Y. Vedmedenko, F. Ummelen, D. Petit, and R. Cowburn 
(2019), Nature Mater. 18, 679.[3] J. A. Arregi, P. Riego, A. Berger, and E.Y. 
Vedmedenko (2023), Nature Commun. 14, 6927.[4] T. Matties, L. Rózsa, L. 
Szunyogh, R. Wiesendanger, and E. Y. Vedmedenko (2024), arXiv:2408.15734.[5] 
M. A. Cascales Sandoval et al. (2023), Appl. Phys. Lett. 123, 
172407. Minden érdeklődőt szívesen látunk! - Everyone is welcome to 
attend.Attila Nagysem-admin AT szfki.hu