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arXiv · 0907.3564

Layered superconductors as negative-refractive-index metamaterials

A. L. Rakhmanov·V. A. Yampol'skii·J. A. Fan·Federico Capasso·Franco Nori
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Abstract

We analyze the use of layered superconductors as anisotropic metamaterials. Layered superconductors can have a negative refraction index in a wide frequency range for arbitrary incident angles. Indeed, low-Tc (s-wave) superconductors allow to produce artificial heterostructures with low losses for T<<Tc. However, the real part of their in-plane effective permittivity is very large. Moreover, even at low temperatures, layered high-Tc superconductors have a large in-plane normal conductivity, producing large losses (due to d-wave symmetry). Therefore, it is difficult to enhance the evanescent modes in either low-Tc or high-Tc superconductors.

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A. L. Rakhmanov, V. A. Yampol'skii, J. A. Fan, Federico Capasso, Franco Nori. 2009-07-23. Layered superconductors as negative-refractive-index metamaterials. https://doi.org/10.1103/physrevb.81.075101

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