• DOI:10.1103/PhysRevB.83.205114
• Corpus ID: 36808502

Metamaterial-enhanced coupling between magnetic dipoles for efficient wireless power transfer

@article{Urzhumov2011MetamaterialenhancedCB,
  title={Metamaterial-enhanced coupling between magnetic dipoles for efficient wireless power transfer},
  author={Yaroslav A. Urzhumov and David R. Smith},
  journal={Physical Review B},
  year={2011},
  volume={83},
  pages={205114}
}

• Y. Urzhumov, David R. Smith
• Published 11 February 2011
• Physics
• Physical Review B

Nonradiative coupling between conductive coils is a candidate mechanism for wireless energy transfer applications. In this paper we propose a power relay system based on a near-field metamaterial superlens and present a thorough theoretical analysis of this system. We use time-harmonic circuit formalism to describe all interactions between two coils attached to external circuits and a slab of anisotropic medium with homogeneous permittivity and permeability. The fields of the coils are found in the point-dipole approximation using Sommerfeld integrals which are reduced to standard special functions in the long-wavelength limit. We show that, even with a realistic magnetic loss tangent of order 0.1, the power transfer efficiency with the slab can be an order of magnitude greater than free-space efficiency when the load resistance exceeds a certain threshold value. We also find that the volume occupied by the metamaterial between the coils can be greatly compressed by employing magnetic permeability with a large anisotropy ratio.