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arXiv · 1902.00248

The field-induced interaction between non-resonant magnetic dipoles

Fang-qi Hu·Qing Zhao·Sheng-Wen Li
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Abstract

We make a general derivation for the magnetic dipole-dipole interaction based on the mediation of the quantized electro-magnetic field. Due to the interaction with the dipoles, the dynamics of the field is added by a dipole field, which finally gives rise to the dipole-dipole interaction. Different from previous studies, the rotating-wave-approximation is no longer needed throughout this derivation, and our result naturally gives the interaction for non-resonant dipoles. Moreover, our derivation also gives the counter-rotating interaction terms, and even the mixed interaction terms between the permanent and transition dipoles. We notice that this field-induced interaction is associated with the interference of the virtual/real photons emitted from the two dipoles, thus the interaction strength could be influenced by the frequency difference of the two dipoles.

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Fang-qi Hu, Qing Zhao, Sheng-Wen Li. 2019-02-01. The field-induced interaction between non-resonant magnetic dipoles. https://doi.org/10.1088/1361-6455/ab6726

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