Superlens with copper and copper oxide

We investigate the imaging properties of copper-based superlens surrounded by copper oxide (Cu${}_2$O). A subwavelength image resolution of the order $\lambda \mathrm{/}9$ is demonstrated theoretically and verified in numerical simulations. It is shown that the existence of excitons in Cu${}_2$O influence the static and dynamical optical properties of the lens. In particular, an improvement of image quality caused by absorption in the spectral region of excitonic resonances is investigated. The plasmon-exciton interaction in the system may pave the way to a tunable, highly nonlinear superlens designs.