Elimination of phase singularity to achieve superresolution in lossy metamaterials

The presence of absorption losses softens the singular behavior of transmission resonances and leads to a good image in spite of limited effective spatial frequency range. Nonetheless, we found that the phase singularity does not disappear despite the considerably reduced retardation effects by softening the transmission resonances. Because the phase singularity severely deteriorates the ideal image reconstruction, broad transmission bandwidth in spatial frequency domain is not sufficient enough to achieve superresolution in TiO ₂ thin film lens. The present work predicts successful elimination of the phase singularity and the achievement of ∼ λ/12.9 superresolution in TiO₂ thin film lens through the phase correction method.