Optical gain removes absorption and increases resolution in a near-field lens

S. Anantha Ramakrishna; J. B. Pendry

doi:10.1103/physrevb.67.201101

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Optical gain removes absorption and increases resolution in a near-field lens

S. Anantha Ramakrishna·J. B. Pendry

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Abstract

A recent paper showed how to construct a lens that focuses near field radiation and hence produce resolution unlimited by wavelength. The prescription requires lossless materials with negative refractive index: finite loss cuts off the finer details of the image. In this paper we suggest compensating for losses by introducing optical gain media into the lens design. Calculations demonstrate a dramatic improvement in performance for a silver/gain composite medium at optical frequencies.

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S. Anantha Ramakrishna, J. B. Pendry. 2002-06-28. Optical gain removes absorption and increases resolution in a near-field lens. https://doi.org/10.1103/physrevb.67.201101

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