Our world is increasingly powered by electricity, which is largely converted to or from mechanical energy using electric motors. Several applications have driven the miniaturization of these machines, resulting in high rotational speeds. Although speeds of several hundred thousand revolutions per minute have been used industrially, we report the realization of an electrical motor reaching 40 million rpm to explore the underlying physical boundaries. Millimeter-scale steel spheres, which are levitated and accelerated by magnetic fields inside a vacuum, are used as a rotor. Circumferential speeds exceeding 1000 m/s and centrifugal accelerations of more than 4 × 10⁸ times gravity were reached. The results open up new research possibilities, such as the testing of materials under extreme centrifugal load, and provide insights into the development of future electric drive systems.

中文翻译：

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磁悬浮宏观钢球的超快旋转。

我们的世界越来越多地由电力驱动，电力通过电动机很大程度上转化为机械能或从机械能转化为机械能。多种应用推动了这些机器的小型化，从而实现了高转速。尽管工业上已经使用了每分钟数十万转的速度，但我们报告了达到4000万转/分钟的电动机的实现，以探索潜在的物理边界。毫米级的钢球被真空中的磁场悬浮和加速，被用作转子。周向速度超过1000 m / s，离心加速度超过4×10 ⁸次达到重力。结果为诸如极端离心负载下的材料测试等新的研究可能性开辟了道路，并为未来的电驱动系统的发展提供了见识。