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arXiv · 2403.13722

Magneto-Ionic Vortices: Voltage-Reconfigurable Swirling-Spin Analog-Memory Nanomagnets

Irena Spasojevic·Zheng Ma·Aleix Barrera·Federica Celegato·Ana Palau·Paola Tiberto·Kristen S. Buchanan·Jordi Sort
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Abstract

Rapid progress in information technologies has spurred the need for innovative memory concepts, for which advanced data-processing methods and tailor-made materials are required. Here we introduce a previously unexplored nanoscale magnetic object: an analog magnetic vortex controlled by electric-field-induced ion motion, termed magneto-ionic vortex or "vortion". This state arises from paramagnetic FeCoN through voltage gating and gradual N3-ion extraction within patterned nanodots. Unlike traditional vortex states, vortions offer comprehensive analog adjustment of key properties such as magnetization amplitude, nucleation/annihilation fields, or coercivity using voltage as an energy-efficient tuning knob. This manipulation occurs post-synthesis, obviating the need for energy-demanding methods like laser pulses or spin-torque currents. By leveraging an overlooked aspect of N3-magneto-ionics -- planar ion migration within nanodots -- precise control of the magnetic layer's thickness is achieved, which enables reversible transitions among paramagnetic, single-domain, and vortion states, offering future prospects for analog computing, multi-state data storage, or brain-inspired devices.

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Irena Spasojevic, Zheng Ma, Aleix Barrera, Federica Celegato, Ana Palau, Paola Tiberto, Kristen S. Buchanan, Jordi Sort. 2024-03-20. Magneto-Ionic Vortices: Voltage-Reconfigurable Swirling-Spin Analog-Memory Nanomagnets. https://doi.org/10.1038/s41467-025-57321-8

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