Superconductors have the unique properties of zero resistance and the Meissner effect. Lenz’s law is a fundamental law of physics. It has occasionally been questioned whether superconductors obey Lenz’s law, and there has not been an explicit answer to this question so far. Recently, we carried out experiments with superconductor coils and a magnet in search of an answer to this question. We found that the interaction between a superconducting coil and a magnet does not comply with one of the primary interpretations of Lenz’s law: the current induced in a circuit due to a change or a motion in a magnetic field is directed so as to exert a mechanical force opposing the motion. Our experimental results show that the induced current in the superconducting coil does not always oppose the motion of the magnet during their interaction. Instead, in a certain portion of the interaction the induced current aids the motion of the magnet. This finding may require the aforementioned interpretation of Lenz’s law to be revised when superconductors are involved.

超导体具有独特的零电阻特性和迈斯纳效应。楞次定律是物理学的基本定律。偶尔有人质疑超导体是否遵守楞次定律，到目前为止，这个问题还没有明确的答案。最近，我们用超导体线圈和磁铁进行了实验，以寻找这个问题的答案。我们发现超导线圈和磁铁之间的相互作用不符合楞次定律的主要解释之一：由于磁场的变化或运动而在电路中感应出的电流被引导以施加机械力反对运动。我们的实验结果表明，超导线圈中的感应电流在它们相互作用期间并不总是反对磁铁的运动。反而，在相互作用的某个部分，感应电流有助于磁铁的运动。当涉及超导体时，这一发现可能需要修改上述楞次定律的解释。