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Abstract The increasing energy demand in information technologies requires novel low‐power procedures to store and process data. Magnetic materials, central to these technologies, are usually controlled through magnetic fields or spin‐polarized currents that are prone to the Joule heating effect. Magneto‐ionics is a unique energy‐efficient strategy to control magnetism that can induce large non‐volatile modulation of magnetization, coercivity and other properties through voltage‐driven ionic motion. Recent studies have shown promising magneto‐ionic effects using nitrogen ions. However, either liquid electrolytes or prior annealing procedures are necessary to induce the desired N‐ion motion. In this work, magneto‐ionic effects are voltage‐triggered at room temperature in solid state systems of CoxMn1‐xN films, without the need of thermal annealing. Upon gating, a rearrangement of nitrogen ions in the layers is observed, leading to changes in the co‐existing ferromagnetic and antiferromagnetic phases, which result in substantial increase of magnetization at room temperature and modulation of the exchange bias effect at low temperatures. A detailed correlation between the structural and magnetic evolution of the system upon voltage actuation is provided. The obtained results offer promising new avenues for the utilization of nitride compounds in energy‐efficient spintronic and other memory devices.
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Magnetic moments and spin structure in single-phase B20 Co 1+x Si 1−x (x = 0.043)
Neutron powder diffraction (NPD) and x-ray magnetic circular dichroism (XMCD) spectroscopy are employed to investigate the magnetism and spin structure in single-phase B20 Co1.043Si0.957. The magnetic contributions to the NPD data measured in zero fields are consistent with the helical order among the allowed spin structures derived from group theory. The magnitude of the magnetic moment is (0.3 ± 0.1) μB/Co according to NPD, while the surface magnetization probed by XMCD at 3 kOe is (0.18–0.31) μB/Co. Both values are substantially larger than the bulk magnetization of 0.11 μB/Co determined from magnetometry at 70 kOe and 2 K. These experimental data indicate the formation of a helical spin phase and the associated conical states in high magnetic fields.
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- PAR ID:
- 10366819
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 131
- Issue:
- 18
- ISSN:
- 0021-8979
- Page Range / eLocation ID:
- Article No. 183902
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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