Left-handed materials do not make a perfect lens.
By means of an analysis on evanescent waves in left-handed materials (LHM), we show that within a slab of such a medium, sandwiched between two positive refraction media, there is amplification of evanescent waves in ideal lossless, dispersiveless media; however, contrary to previous claims, this is limited to a finite width of the slab so that it prevents their restoration and perfect focusing. We illustrate this by considering their coupling to propagating waves through a tunnel barrier containing a slab of LHM. Further, we show that the effect of absorption, necessarily present in such materials, may drastically change any evanescent amplifying wave into a decaying one.
Garcia
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Laboratorio de Fisica de sistemas Pequeños, Consejo Superior de Investigaciones Cientificas, Serrano 144, Madrid 28006, Spain. nicolas.garcia@fsp.csic.es
Nieto-Vesperinas
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