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Metamaterials proposed as perfect magnetoelectrics

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 Added by Schneider Andreas
 Publication date 2010
  fields Physics
and research's language is English




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Magnetoelectric susceptibility of a metamaterial built from split ring resonators have been investigated both experimentally and within an equivalent circuit model. The absolute values have been shown to exceed by two orders of magnitude that of classical magnetoelectric materials. The metamaterial investigated reaches the theoretically predicted value of the magnetoelectric susceptibility which is equal to the geometric average of the electric and magnetic susceptibilities.



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We demonstrate that there is a strong diamagnetic response of metamaterials, consisting of open or closed split ring resonators (SRRs). Detailed numerical work shows that for densely packed SRRs the magnetic permeability, $mu(omega)$, does not approach unity, as expected for frequencies lower and higher than the resonance frequency, $omega_0$. Below $omega_0$, $mu(omega)$ gives values ranging from 0.9 to 0.6 depending of the width of the metallic ring, while above $omega_0$, $mu(omega)$ is close to 0.5. Closed rings have $muapprox 0.5$ over a wide frequency range independently of the width of the ring. A simple model that uses the inner and outer current loop of the SRRs can easily explain theoretically this strong diamagnetic response, which can be used in magnetic levitation.
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