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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]

Abstract The design of sub-wavelength structure with full-spectrum near-unity solar absorption is a long-sought-after goal of crucial importance for optoelectronic materials and technology. To date, numerous attempts to tackle this problem consisted either of using stronger absorption-but narrowband or the broader spectrum-but moderate light trapping mechanisms. Herein, a novel strategy that achieves perfect absorption for solar energy in the full-spectrum range of the sun's radiance is presented by the thin-film refractory metal resonators. This impressive absorption mainly stems from the cooperative effect of strong plasmonic resonances and the intrinsic broadband spectral responses by the refractory metals, such as Ti, V, W, etc. The full-spectrum weighted solar absorption efficiency is exceeding 98%, showing a near-unity light trapping for the sun's radiation. Moreover, excellent thermal emitting with the spectral averaged efficiency ~ 91% is achieved in the wavelength range (280–4000 nm) by the W-based absorber, suggesting a platform for near-perfect blackbody emitting source. More importantly, the investigations on achieving full-spectrum solar absorbers and thermal emitters provide new insight on the mechanism and philosophy for the design. Just like the proverb, in order to catch bandits, the first thing is to catch the ringleader. As for the purpose of achieving full-spectrum near-unity absorbers or radiators, the key point is to perfectly trap or excite the solar/thermal power in the main distribution ranges for the sunlight or the blackbody radiation. Accordingly, these attractive properties and findings suggest that the investigation and the related full-spectrum solar absorbers and blackbody radiator might have promising applications in the fields related to energy harvesting and conversion. Graphical abstract fx1 Highlights • A feasible way is demonstrated for achieving full-spectrum thin-film solar absorbers. • The averaged solar absorption efficiency η A is > 98% for the sunlight (280–4000 nm). • Near-perfect thermal emitter with similar properties to the ideal blackbody radiator is demonstrated. • The key important factor for designing near-unity full-spectrum absorber/ emitter is obtained. [ABSTRACT FROM AUTHOR]