Ye Xinglong, Singh Harish K, Zhang Hongbin, Geßwein Holger, Chellali Mohammed Reda, Witte Ralf, Molinari Alan, Skokov Konstantin, Gutfleisch Oliver, Hahn Horst, Kruk Robert
Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344, Eggenstein-Leopoldshafen, Germany.
Institute of Materials Science, Technische Universität Darmstadt, 64287, Darmstadt, Germany.
Nat Commun. 2020 Sep 24;11(1):4849. doi: 10.1038/s41467-020-18552-z.
Owing to electric-field screening, the modification of magnetic properties in ferromagnetic metals by applying small voltages is restricted to a few atomic layers at the surface of metals. Bulk metallic systems usually do not exhibit any magneto-electric effect. Here, we report that the magnetic properties of micron-scale ferromagnetic metals can be modulated substantially through electrochemically-controlled insertion and extraction of hydrogen atoms in metal structure. By applying voltages of only ~ 1 V, we show that the coercivity of micrometer-sized SmCo, as a bulk model material, can be reversibly adjusted by ~ 1 T, two orders of magnitudes larger than previously reported. Moreover, voltage-assisted magnetization reversal is demonstrated at room temperature. Our study opens up a way to control the magnetic properties in ferromagnetic metals beyond the electric-field screening length, paving its way towards practical use in magneto-electric actuation and voltage-assisted magnetic storage.
由于电场屏蔽作用，通过施加小电压来改变铁磁金属的磁性仅限于金属表面的几个原子层。大块金属系统通常不表现出任何磁电效应。在此，我们报告微米级铁磁金属的磁性可以通过电化学控制氢原子在金属结构中的插入和提取而得到显著调制。通过仅施加约1 V的电压，我们表明作为大块模型材料的微米级SmCo的矫顽力可以可逆地调节约1 T，比先前报道的大两个数量级。此外，在室温下证明了电压辅助的磁化反转。我们的研究开辟了一种在超出电场屏蔽长度的情况下控制铁磁金属磁性的方法，为其在磁电驱动和电压辅助磁存储中的实际应用铺平了道路。
