BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Memento EPFL// BEGIN:VEVENT SUMMARY:IMX Seminar Series - Exploring three dimensional spin systems – and beyond DTSTART:20241118T131500 DTEND:20241118T141500 DTSTAMP:20260921T194900Z UID:013cd2768e41a4a92df978f062bb2d48cbc84162645396e075dc35c6 CATEGORIES:Conferences - Seminars DESCRIPTION:Dr. Claire Donnelly\, Max Planck Institute for Chemical Physic s of Solids in Dresden\, Germany\nThree dimensional magnetic systems promi se significant opportunities for applications\, for example providing high er density devices and new functionalities associated with complex topolog y and greater degrees of freedom [1\,2]. Extending to three dimensions all ows for the formation of new topologies of spin textures\, for example con taining defects in 3D such as Bloch point singularities\, or truly three-d imensional topological structures such as magnetic hopfions.\nIn this talk \, I will address two main questions: first\, can we observe and understan d such three-dimensional topological magnetic textures\, and second\, can we control them?\nFor the observation and understanding of these three-dim ensional textures\, we have developed magnetic X-ray tomographic technique s\, that open the possibility to map both the three-dimensional magnetic s tructure [3]\, and its dynamical response to external excitations [4\,5].   In this way\, we observe 3D magnetic solitons which we identify as nano scale magnetic vortex rings\, as well as torons that contain Bloch point s ingularities [6\,7].\nHowever\, while X-ray magnetic tomography is now a r elatively well-established technique\, high resolution imaging of extended magnetic systems has so far been limited to rare-earth containing materia ls. To this end\, I will present recent results of soft X-ray dichroic pty chography where the phase dichroism offers a route to imaging magnetic sys tems that until now have not been accessible [8].\nAs well as naturally ex isting within the bulk\, 3D spin textures can be introduced and controlled via the patterning of 3D curvilinear geometries [9]. In this way\, not on ly can new states be realized [10]\, but the energy landscape of topologic al defects can be designed through the local patterning of curvature induc ed chirality [11].\nThis new understanding and control of topological text ures in 3D magnetic systems paves the way not only for enhanced understand ing of these systems\, but also towards the next generation of technologic al devices.\n\n\nReferences\n\n[1] Fernández-Pacheco et al.\, Nature Comm unications 8\, 15756 (2017).\n[2] C. Donnelly and V. Scagnoli\, J. Phys. D : Cond. Matt. 32\, 213001 (2020).\n[3] C. Donnelly et al.\, Nature 547\, 3 28 (2017).\n[4] C. Donnelly et al.\, Nature Nanotechnology 15\, 356 (2020) .\n[5] S. Finizio et al.\, Nano Letters (2022)\n[6] C. Donnelly et al.\, N at. Phys. 17\, 316 (2020)\n[7] N. Cooper\, PRL. 82\, 1554 (1999).\n[8] J. Neethirajan et al.\, Phys. Rev. X 14\, 031028 (2024)\n[9] D. Sheka et al.\ , APL 118\, 230502 (2021)\n[10] C. Donnelly et al.\, Nature Nanotechnology 17\, 136 (2022)\n[11] S. Ruiz Gomez et al.\, arXiv:2404.06042 [cond-mat.m es-hall]\n\nBio: Following her MPhys at the University of Oxford\, Claire went to Switzerland to carry out her PhD studies at the Paul Scherrer Inst itute and ETH Zurich. She was awarded her PhD in 2017 for her work on 3D s ystems\, in which she developed X-ray magnetic tomography\, work that was recognised by a number of awards.\nAfter a postdoc at the ETH Zurich\, sh e moved to the University of Cambridge and the Cavendish Laboratory as a L everhulme Early Career Research Fellow\, where she focused on the behaviou r of three dimensional magnetic nanostructures.\nSince September 2021 she is a Lise Meitner Group Leader of Spin3D at the Max Planck Institute for C hemical Physics of Solids in Dresden\, Germany. Her group focuses on the physics of three dimensional magnetic and superconducting systems.\n  LOCATION:MXF 1 https://plan.epfl.ch/?room==MXF%201 STATUS:CONFIRMED END:VEVENT END:VCALENDAR