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arXiv · 1206.1683

Strategy for designing broadband epsilon-near-zero metamaterial with loss compensation by gain media

Lei Sun·Kin Wah Yu
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Abstract

A strategy is proposed to design the broadband gain-doped epsilon-near-zero (GENZ) metamaterial. Based on the Milton representation of effective permittivity, the strategy starts in a dimensionless spectral space, where the effective permittivity of GENZ metamaterial is simply determined by a pole-zero structure corresponding to the operating frequency range. The physical structure of GENZ metamaterial is retrieved from the pole-zero structure via a tractable inverse problem. The strategy is of great advantage in practical applications and also theoretically reveals the cancellation mechanism dominating the broadband near-zero permittivity phenomenon in the spectral space.

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Lei Sun, Kin Wah Yu. 2012-06-08. Strategy for designing broadband epsilon-near-zero metamaterial with loss compensation by gain media. https://doi.org/10.1063/1.4730380

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