Three-dimensional (3D) magnetic architectures are emerging platforms for accessing new spin textures and spin-wave functionalities, while offering routes toward higher integration density in spin-based devices [1,2]. In this talk, I will present 3D ferromagnetic Ni woodpile nanonetworks fabricated by a scalable approach combining two-photon lithography (TPL) and conformal atomic layer deposition (ALD) [3].

I will discuss how geometry and finite size influence the static magnetic configurations and dynamic magnonic response of these 3D nanonetworks. Magnetic force microscopy reveals distinct remanent spin textures in structures with different numbers of vertical unit-cell repetitions, while Brillouin light scattering measurements show corresponding changes in resonance frequency, mode localization, and spatial mode distribution. These results show that the underlying 3D architecture can strongly shape the magnonic response, even at the top surface of nominally similar nanotubes.

I will further present two complementary routes for coherent spin-wave excitation in additively manufactured 3D magnonic crystals. In a narrowband approach, the full 3D crystal is embedded in a planar microwave microresonator and probed by microresonator ferromagnetic resonance at discrete RF frequencies [4]. In a broadband approach, 3D crystals are integrated onto coplanar waveguides for RF excitation, while micro-focused Brillouin light scattering provides spatially resolved optical detection. Supported by micromagnetic simulations, these results highlight practical routes toward coherent, integrated, and reconfigurable 3D magnonic devices.

References:
[1] A. Fernández-Pacheco, R. Streubel, O. Fruchart, et al., Nature Communications 8 (2017).
[2] G. Gubbiotti et al., Journal of Physics: Condensed Matter 37 (2025).
[3] H. Guo, A. J. M. Deenen, M. Xu, M. Hamdi, and D. Grundler, Advanced Materials 35 (2023).
[4] H. Guo, K. Lenz, M. Gołębiewski, et al., Small 22 (2026).