Optical Metasurface Based on Subwavelength Nanoplasmonic Metamaterial-Lined Apertures

We demonstrate the design and nanofabrication of a new class of metasurface based on arrays of densely packed subwavelength apertures made to resonate through the inclusion of nanostructured plasmonic epsilon-negative and near-zero metamaterials. These metasurfaces exhibit high-contrast fano-like resonance-antiresonance transmission profiles with polarization insensitivity and extreme versatility in design. The proposed metasurfaces push the boundaries of current top-down nanofabrication technologies with sub-10-nm features, and are ideal for a wide variety of innovative applications throughout the electromagnetic spectrum, including subwavelength imaging for material characterization, planar phase-gradient mirrors for cavity quantum electrodynamics, and fully optical switches for integrated optical systems. We report a metasurface design operating in the near-infrared region (150–300 THz) with a typical unit-cell electrical size of one fifth of the free-space wavelength and a remarkable resonance-antiresonance contrast of up to 35 dB.