Optical and dielectric anisotropies of nematic liquid crystals are key properties in controlling light transmission when implemented with polarizers. On the other hand, optical metamaterial is artificial nano-structure composed of subwavelength inclusions permitting a variety of new optical functions. Combination of nematics with optical metamaterial leads to an optical device structure where transmission and reflection can be controlled by optical and electrical means. By constructing an optical metamaterial with optical anisotropy, nematics permits electric control of reflection and transmission. When V-shaped nano-antennas are introduced, anomalous refraction can also be electrically controlled by employing nematics. Rapid phase change of a light beam in a phase-discontinuity optical metamaterial leads to a strong deflection of beam path allowing observation of optical spin Hall effect. When nematics are placed in the beam path, post-selection in weak measurement can be electrically tuned, which allow an electric control of optical spin Hall transverse shift in optical metamaterial. Furthermore, a thin film of organics is shown to be a new epsilon-near-zero metamaterial. Molecular structure possessing a strong coupling between two neighboring excitons shows an epsilon-near-zero response, owing to superposition of large numbers of Lorentzian oscillators in a narrow spectral range.
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