Magnetic Soft X-ray Tomography Study of Gaussian Curvature Induced Chirality in Topological Spin Textures

We propose to use the MISTRAL Beamline to image the three-dimensional spin structure of Co/Pd films sputtered onto customized curvature arrays featuring regions of positive, negative, and zero Gaussian curvature. Tailoring the local energy landscape to stabilize magnetic textures such as chiral domain walls (DWs) and skyrmions offers an exciting pathway for advancing nanomagnetic devices toward new functionalities. While much progress has been made in understanding these textures in two-dimensional systems and thin films, the role of curvature remains largely unexplored. In recent work on the MISTRAL Beamline, our group showed that curvature induces an effective Dzyaloshinskii–Moriya interaction (DMI), resulting in an increase of roughly one-third of the intrinsic DMI compared to planar films. To more firmly establish curvature-induced DMI, we aim to (1) tune the DMI in planar Co/Pd films to zero by adjusting the Pd thickness and explore how positive and negative Gaussian curvature lead to opposite DMI and domain wall chirality, and (2) quantitatively determine how the magnitude of curvature influences the strength of the induced DMI. The proposed curvature-array structures are fabricated using two-photon lithography (2PL), and micromagnetic simulations in MuMax+ provide further support by confirming that Gaussian curvature sign governs the preferred chirality of spin textures. MISTRAL’s unique capabilities allow for tomographic reconstructions of spin configurations in 3D magnetic systems with high spatial and spectral resolution, and with exceptional magnetic sensitivity due to its X-ray polarization modulation scheme, making it ideally suited for our studies. Access to the MISTRAL beamtime would enable us to quantitatively investigate the relationship between curvature and spin textures, paving the way for the design of next-generation 3D nanomagnetic devices.