Negative Refractive Index in Optics of Metal-Dielectric Composites
نویسندگان
چکیده
Specially designed metal-dielectric composites can have a negative refractive index in the optical range. Specifically, it is shown that arrays of single and paired nanorods can provide such negative refraction. For pairs of metal rods, a negative refractive index has been observed at 1.5 μm. The inverted structure of paired voids in metal films may also exhibit a negative refractive index. A similar effect can be accomplished with metal strips in which the refractive index can reach −2. The refractive index retrieval procedure and the critical role of light phases in determining the refractive index is discussed. OCIS codes: 160.4760, 260.5740, 310.6860
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