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L. Flajsman, K. Wagner, M. Vaňatka, J. Gloss, V. Křizáková, M. Schmid, H. Schultheiss, M. Urbanek:
"Zero-field propagation of spin waves in waveguides prepared by focused ion beam direct writing";
Physical Review B, 101 (2020), 0144361 - 0144367.

Metastable face-centered-cubic Fe78Ni22thin films are excellent candidates for focused ion beam directwriting of magnonic structures due to their favorable magnetic properties after ion-beam-induced transformation.The focused ion beam transforms the originally nonmagnetic fcc phase into the ferromagnetic bcc phase withadditional control over the direction of uniaxial magnetic in-plane anisotropy and saturation magnetization. Localmagnetic anisotropy direction control eliminates the need for external magnetic fields, paving the way towardscomplex magnonic circuits with waveguides pointing in different directions. In the present study, we show thatthe magnetocrystalline anisotropy in transformed areas is strong enough to stabilize the magnetization in thedirection perpendicular to the long axis of narrow waveguides. Therefore, it is possible to propagate spin wavesin these waveguides in the favorable Damon-Eshbach geometry without the presence of any external magneticfield. Phase-resolved microfocused Brillouin light scattering yields the dispersion relation of these waveguidesin zero as well as in nonzero external magnetic fields

http://dx.doi.org/10.1103/PhysRevB.101.014436