Perfect absorption and phase singularities induced by surface lattice resonances for plasmonic nanoparticle array on a metallic film

Abstract

The formation of pairs of perfect absorption associated with phase singularities in the parameter space using the hybridized structure constructed with a metallic nanoparticle array and a metallic film is promising to enhance light-mater interactions. However, the localized plasmon resonances of the array possess strong radiative losses, which is an obstacle to improve the performances for many applications. On the contrary with the subwavelength array hybridized structure, this study shows that by enlarging the lattice spacing, the oscillator strength of the nanoparticles can be enhanced with the formation of surface lattice resonance, thereby leading to similar but much narrower pairs of perfect absorption due to the interactions with the Fabry-Pérot cavity modes. Furthermore, when the surface plasmon polariton mode shift to the same spectral range associated with the enlarged lattice spacing, the coupling and mode hybridization with the surface lattice resonance result in an anticrossing in the spectra. Although the resonance coupling does not enter the strong coupling regime, the quality factors (∼ 134) and near-field enhancements (∼ 44) are strongly enhanced for the hybridized resonance modes due to the effectively suppressed radiative losses compared with that of the localized plasmon resonances, which make the hybridized structure useful for the design of functional nanophotonic device such as biosensing, multi-model nanolasing, and high-quality imaging.

Ultrasensitive Refractive Index Sensing Based on Hybrid High-Q Metasurfaces

“…This mode is determined by the coupling between the individual cuboid and the metallic film (specifically, the surface plasmon polariton (SPP) modes). The surface lattice resonance (SLR) modes of the array cannot be effectively excited due to the image charges created by the Au film . As the height h increases, the incident light can more effectively couple with the diffracted orders in the plane of the arrays and is able to excite the SLR mode. − When the height h is large enough, a second SLR mode appears.…”

Impact of Optical Cavity on Refractive Index Sensitivity of Gold Nanohole Arrays

“…Further, the resonance linewidth can be reduced by coupling plasmons to a system with a narrow resonance, such as photonic cavity, due to the modified photonic density of states. This effect has been demonstrated in various systems, including gold nanorods [18], nanodisks [19], and nanorings [20] positioned above a gold mirror. However, to the best of our knowledge, there is currently no data available on the impact of coupling in the NHAs-photonic cavity system on refractive index sensing performance.…”

Perfect Absorption with Independent Electric and Magnetic Lattice Resonances in Metallo‐Dielectric Arrays

“…One solution to overcome this limit is to place the arrays in the proximity of a perfectly reflective surface, in a configuration known as a "Salisbury screen", [39,44,45] for which perfect absorption can be achieved if the separation between mirror and array is adequately chosen. [46] However, this configuration completely blocks the transmission of light at all wavelengths, which can be detrimental for applications in which perfect absorption is required only for a certain wavelength range while perfect transmission is desired for the rest. The unit cell (shaded area) is a rectangle with sides of length a x and a y , with the gold and silicon nanoparticles located, respectively, at the origin (x 1 = 0, y 1 = 0) and at the center (x 2 = a x /2, y 2 = a y /2) of it.…”