A minimal discrete model for toroidal moments and its experimental realization

@article{Xiang2017AMD,
  title={A minimal discrete model for toroidal moments and its experimental realization},
  author={Hong Xiang and Lixin Ge and Liang Liu and Tianshu Jiang and Z. Q. Zhang and C. T. Chan and Dezhuan Han},
  journal={Physical Review B},
  year={2017},
  volume={95},
  pages={045403}
}
It is well known that a closed loop of magnetic dipoles can give rise to the rather elusive toroidal moment. However, artificial structures required to generate the necessary magnetic moments in metamaterials are typically optically large, complex to make, and easily compromised by the kinetic inductance at high frequencies. Instead of using magnetic dipoles, we propose a minimal model based on just three aligned discrete electric dipoles in which the occurrence of resonant toroidal modes is… 

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