Controlling magnetism, essential for a wide-range of technologies, is impaired by the impossibility of generating a maximum of magnetic field in free space. Here, we propose a strategy based on negative permeability to overcome this stringent limitation. We experimentally demonstrate that an active magnetic metamaterial can emulate the field of a straight current wire at a distance. Our strategy leads to an unprecedented focusing of magnetic fields in empty space and enables the remote cancellation of magnetic sources, opening an avenue for manipulating magnetic fields in inaccessible regions.

中文翻译：

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在难以接近的区域调整磁场

由于无法在自由空间中产生最大的磁场，因此对广泛的技术必不可少的磁性控制受到了损害。在这里，我们提出了一种基于负磁导率的策略来克服这一严格限制。我们通过实验证明了一种有源磁性超材料可以在一定距离上模拟直流电流线的场。我们的策略导致空域磁场的空前集中，并实现了远程消除磁场源，为在难以接近的区域操纵磁场开辟了道路。