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Long-range magnetic interaction due to the Casimir effect

P. Bruno
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Abstract

The zero-point quantum fluctuations of the electromagnetic field in vacuum are known to give rise to a long-range attractive force between metal plates (Casimir effect). For ferromagnetic layers separated by vacuum, it is shown that the interplay of the Casimir effect and of the magneto-optical Kerr effect gives rise to a long-range magnetic interaction. The Casimir magnetic force is found to decay as $D^{-1}$ in the limit of short distances, and as $D^{-5}$ in the limit of long distances. Explicit expressions for realistic systems are given in the large and small distance limits. An experimental test of the Casimir magnetic interaction is proposed.

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P. Bruno. 2002-05-27. Long-range magnetic interaction due to the Casimir effect. https://doi.org/10.1103/physrevlett.88.240401

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