Electromagnetic Field Enhancement in Small Gaps: A Rigorous Mathematical Theory

  title={Electromagnetic Field Enhancement in Small Gaps: A Rigorous Mathematical Theory},
  author={Junshan Lin and Fernando Reitich},
  journal={SIAM J. Appl. Math.},
This paper is concerned with the field enhancement when an electromagnetic wave passes through subwavelength metallic gaps. We focus on a particular configuration when there is extreme scale difference between the wavelength of the incident wave, the thickness of metal films, and the size of gap apertures. Based upon a rigorous study of the perfect electrical conductor model for the transverse magnetic ploarization, we show that enormous electric field enhancement occurs inside the gap if the… 

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