Plasmonic focusing lens based on single-turn nano-pinholes array

Abstract

A miniature, simplified and planar plasmonic lens based on the circular array of nano-pinholes for on-axis beaming has been proposed and investigated systematically in the visible spectrum. Focusing properties of the designed plasmonic lens illuminated under circular polarized (CP) light for different radius of circular ring, filled with different dielectrics, with different numbers of pinholes have been investigated and analyzed in detail by finite element method (FEM). Our simulated results demonstrate such a miniature single-turn structure can also generate a totally centrosymmetric focusing spot under the CP illumination. Besides, by properly manipulating the filled dielectric and incident wavelengths, enhanced transmission, elongated depth of focus have also be realized, which can be used to modulate the transmitting fields effectively. Such a miniature and simplified plasmonic focusing lens can open up a vital path toward fiber-end planar photonic devices for biosensing and imaging.

HgCdTe mid-Infrared photo response enhanced by monolithically integrated meta-lenses

“…Meta-surface has been successfully applied to control the phase, amplitude and polarization of the incident light by altering the shape and the size of each meta-unit and arranging them a proper way. In a wide range of spectrum from the visible to the terahertz band [13][14][15][16][17][18][19][20][21][22][23][24] , many optical applications based on meta-surfaces have been realized and reported, including meta-surface lenses (meta-lenses), waveplates, holograms and polarimeters [25][26][27][28][29][30][31][32] . The ultra-compact sizes of the flat optics make them promising to substitute conventional ones in some situations.…”

Fano feature induced by a bound state in the continuum via resonant state expansion

“…We believe that extending our theoretical approach to the Brewster BIC could be an interesting topic for the future studies. Nowadays, the BICs in photonic systems have already found important applications in enhanced optical absorbtion 57 , surface enhanced Raman spectroscopy 58 , lasing 59 , and sensors 60 . We speculate that analytic results are of importance for a further insight into localization of light as well as the concurrent phenomenon of collapsing Fano resonance.…”

Fano feature induced by a bound state in the continuum via resonant state expansion

“…In particular we expect that the resonant approximation can be invoked to build a rigorous theory of nonlinear response 55 . The BICs in photonic systems have already found important applications in enhanced optical absorbtion 56 , surface enhanced Raman spectroscopy 57 , lasing 58 , and sensors 59 . We speculate that analytic results are of importance for a further insight into localization of light as well as the concurrent phenomenon of collapsing Fano resonance.…”