Spin-wave eigenmodes in direct-write 3D nanovolcanoes

O. V. Dobrovolskiy; N. R. Vovk; A. V. Bondarenko; S. A. Bunyaev; S. Lamb-Camarena; N. Zenbaa; R. Sachser; S. Barth; K. Y. Guslienko; A. V. Chumak; M. Huth; G. N. Kakazei

doi:10.1063/5.0044325

arXiv · 2102.03574

Spin-wave eigenmodes in direct-write 3D nanovolcanoes

O. V. Dobrovolskiy·N. R. Vovk·A. V. Bondarenko·S. A. Bunyaev·S. Lamb-Camarena·N. Zenbaa·R. Sachser·S. Barth·K. Y. Guslienko·A. V. Chumak·M. Huth·G. N. Kakazei

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Abstract

Extending nanostructures into the third dimension has become a major research avenue in modern magnetism, superconductivity and spintronics, because of geometry-, curvature- and topology-induced phenomena. Here, we introduce Co-Fe nanovolcanoes-nanodisks overlaid by nanorings-as purpose-engineered 3D architectures for nanomagnonics, fabricated by focused electron beam induced deposition. We use both perpendicular spin-wave resonance measurements and micromagnetic simulations to demonstrate that the rings encircling the volcano craters harbor the highest-frequency eigenmodes, while the lower-frequency eigenmodes are concentrated within the volcano crater, due to the non-uniformity of the internal magnetic field. By varying the crater diameter, we demonstrate the deliberate tuning of higher-frequency eigenmodes without affecting the lowest-frequency mode. Thereby, the extension of 2D nanodisks into the third dimension allows one to engineer their lowest eigenfrequency by using 3D nanovolcanoes with 30% smaller footprints. The presented nanovolcanoes can be viewed as multi-mode microwave resonators and 3D building blocks for nanomagnonics.

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O. V. Dobrovolskiy, N. R. Vovk, A. V. Bondarenko, S. A. Bunyaev, S. Lamb-Camarena, N. Zenbaa, R. Sachser, S. Barth, K. Y. Guslienko, A. V. Chumak, M. Huth, G. N. Kakazei. 2021-02-06. Spin-wave eigenmodes in direct-write 3D nanovolcanoes. https://doi.org/10.1063/5.0044325

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