Kruchkov A J, White J S, Bartkowiak M, Živković I, Magrez A, Rønnow H M
Department of Physics, Harvard University, Cambridge, MA, 02138, USA.
Laboratory for Quantum Magnetism (LQM), Insititute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
Sci Rep. 2018 Jul 11;8(1):10466. doi: 10.1038/s41598-018-27882-4.
Magnetic skyrmions are topologically protected spin-whirls currently considered as promising for use in ultra-dense memory devices. Towards achieving this goal, exploration of the skyrmion phase response and under external stimuli is urgently required. Here we show experimentally, and explain theoretically, that in the magnetoelectric insulator CuOSeO the skyrmion phase can expand and shrink significantly depending on the polarity of a moderate applied electric field (few V/μm). The theory we develop incorporates fluctuations around the mean-field that clarifies precisely how the electric field provides direct control over the free energy difference between the skyrmion and the surrounding conical phase. The quantitative agreement between theory and experiment provides a solid foundation for the development of skyrmionic applications based on magnetoelectric coupling.
磁斯格明子是一种拓扑保护的自旋涡旋，目前被认为有望用于超密集存储设备。为了实现这一目标，迫切需要探索斯格明子相在外部刺激下的响应。在这里，我们通过实验表明，并从理论上解释，在磁电绝缘体CuOSeO中，斯格明子相可以根据适度施加电场（几伏/微米）的极性显著地扩展和收缩。我们发展的理论纳入了围绕平均场的涨落，精确地阐明了电场如何直接控制斯格明子与周围锥形相之间的自由能差。理论与实验之间的定量一致性为基于磁电耦合的斯格明子应用的发展提供了坚实的基础。
