Superconductor magnetism effect on gold

[MattEU]

Physicists in the UK have shown that a superconductor can transfer a magnetic field from a magnet to a non-magnetic metal without becoming magnetized itself. The surprising effect is not predicted by any prevailing theory of superconductivity and could have important applications in the emerging field of superconducting spintronics.

... What the researchers found surprised them. They found no evidence of a magnetic field inside the superconductor, but they did see a magnetic field in the gold – even though gold is not normally magnetic. In other words, a magnet on one side of a superconductor can induce a magnetic field on the other side of the superconductor – even though there is no field within the superconductor. Furthermore, the researchers found that the induced magnetic field in the gold depended on the relative orientation of the fields in the two magnetic layers on the opposite side of the superconductor. When the two fields were perpendicular, a strong field was induced. When they were parallel, however, the effect was almost zero.

... Robinson says that of the three explanations the researchers posit, the most likely is the generation of spin-polarized Cooper pairs and their transmission through the superconductor.

Superconductor induces magnetism in non-magnetic gold