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In this work, we for the first time propose and demonstrate a feasible strategy for multi-band ultra-narrow optical transmission of the plasmonic crystals by introducing a high-index dielectric (HID) cavity, which can be acted as an efficient optical field coupling and hybridization component. Five sharp transmission bands with the maximal bandwidth of 6.5 nm are achieved. High spectral Q-factor of 327 with the corresponding bandwidth of 2.8 nm is observed in the optical region. These features pave a simple and universal way for multispectral narrowband optical transmission based on the typical plasmonic crystals. [ABSTRACT FROM AUTHOR]

Materials with ultra-narrowband light transparent window are desirable for applications in optoelectronics. Due to the intrinsic loss in the traditional metallic nanostructures, the plasmonic or electromagnetically induced light transparent spectrum is with a typically broad bandwidth. In this work, a novel strategy for achieving ultra-narrowband optical transparent window is theoretically proposed and demonstrated based on the dielectric dimer resonators metamolecule array. Owing to the electromagnetic resonant coupling in this lossless all-dielectric metamolecule, a transparent window with the bandwidth down to nanometer scale and the spectral slope up to 71%/nm is achieved. The obtained optical properties can be manipulated in the spectral range by adjusting the structural parameters and dielectric permittivity. These findings pave a new way for sharp narrowband transparent window with potential applications in filtering, optical manipulation, etc. [ABSTRACT FROM AUTHOR]

Highly conductive metal film structures with light transparency are of great importance for practical applications in optoelectronics. Here we investigate the feasible way for tuning the intrinsic opaque continuous metal film to be optical transparency by using a dielectric layer. The introduced dielectric acts as a resonant cavity and supports strong optical field coupling capability. In comparison with the nearly opaque response of the original metal film, transmission enhancement factor up to 2300% with the maximal transmittance of 78% are achieved in the dielectric cavity coupled metal film system. Moreover, it is observed that the multiband light transmission behavior can be highly scaled by tuning the cavity length. These impressive optical properties suggest the proposed motif to be a new alternative way for achieving transparent and highly conducting metal film structures with potential applications in transparent conductors, plasmonic filters and images. [ABSTRACT FROM AUTHOR]

Artificial manipulation of light is significant for the material science and technology. In this work, noticeably enhanced light absorption with absorption above 99% has been demonstrated in a deep-subwavelength meta-surface structure. Dipolar plasmon resonance and near-field coupling of the plasmons between the adjacent core–shell metallo-dielectric spheres together with the optical field coupling by the dielectric shells are the main contributions for the multispectral light absorption. The predicted structure can be fabricated in large-area based on the standard colloidal self-assembled method and the metal deposition technique. These optical and structural features hold the proposed platform to be a potential of the application in light modulation and absorption and other optoelectronics. [ABSTRACT FROM AUTHOR]

Multi-band light perfect absorbers formed by metal-semiconductor materials are desirable for optoelectronics and have been long pursued. In this work, we numerically propose and demonstrate a four-band resonant near-perfect light absorption by utilizing the aluminum ring intercalated with silicon disk array, which can support strong plasmonic resonances and optical cavity modes. The multi-band near-perfect absorption can be tuned by the structural parameters and the maximal absorption is exceeding 99.8%. These features lay a foundation for low-cost optoelectronic technologies since the semiconductor silicon cavities are currently very important elements in the field of photonics. [ABSTRACT FROM AUTHOR]

In this work, we theoretically propose and numerically demonstrate a novel multi-band subtractive filtering platform by utilizing the dielectric resonators. In addition, the plasmon-like hotspots are also observed in this dielectric structure. Multi-band light filtering can be quantitatively adjusted by the polarization state and the classical Malus law is verified in this dielectric structure. These findings lay a foundation for multispectral optical behaviors and hold applications in the nanophotonics. [ABSTRACT FROM AUTHOR]

Plasmonic–colloidal crystals are with unique optical properties due to the combination of the plasmonic and photonic features. In this paper, we demonstrate a novel dual-band plasmonic refractometric sensing motif by using a metal film coated colloidal crystal (CC) intercalated with a silicon (Si) layer (M–Si–CC), where the Si layer can simultaneously couple with the top plasmonic crystal and the bottom CC. Distinct sensing behaviors of the two transmittance peaks are observed. In addition, significantly improved sensitivity is achieved in comparison with those of the conventional metal coated CCs (M–CCs). Moreover, the structure is with quite simple design and could be fabricated in a straightforward manner over large areas. These features hold the proposed motif with potential applications in multispectral biosensing and detection. [ABSTRACT FROM AUTHOR]

Ultra-narrowband light filtering is with wide applications in display, image and optical measurement devices. Here, we theoretically propose and show a new and simple strategy for achieving notch filters by sub-wavelength all-dielectric meta-materials (ADMMs). The ADMM is comprised of a triple-layered high/low/high-index dielectric structure. Similar to the plasmonic resonances existed in the metallic meta-materials, strong optical field resonances have been observed in this ADMM. Dual-band reflective notch filtering phenomenon is achieved. Spectral bandwidth down to 3 nm and the spectral contrast reaching 97% are obtained. Moreover, the polarization-independent response is simultaneously achieved in this ADMM. Furthermore, high spectral tunability for the observed ultra-narrowband filtering is obtained via tuning the structural parameters. [ABSTRACT FROM AUTHOR]