Active, right-handed media exist for which the refractive index is negative in a finite bandwidth. We propose a lumped circuit model for such media, based on a resonant transmission line with negative shunt resistance.
© 2005 Optical Society of America
B. Nistad and J. Skaar, "Lumped Circuit Model for an Active Right-Handed Medium with Negative Refractive Index," in Photonic Metamaterials: From Random to Periodic, Technical Dgest (CD) (Optical Society of America, 2006), paper WD15.
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