Optimizing the superlens: manipulating geometry to enhance the resolution

Article appears in Applied Physics Letters (http://apl.aip.org/) and is copyrighted by American Institute of Physics (http://www.aip.org/).We analyze the performance of a planar lens based on realistic negative index material in a\ud generalized geometry. We demonstrate that the conventional superlens design (where the lens is\ud centered between the object and the image) is not optimal from the resolution point of view, develop\ud an analytical expression for the resolution limit of a generalized lens, use it to find the optimum lens\ud configuration, and calculate the maximum absorption practical nearfield superlenses may have. We\ud demonstrate that in contrast to the conventional superlens picture, planar imaging is typically\ud accompanied by excitation of surface waves at both interfaces of the lens