Enhancement of focusing energy of ultra-thin planar lens through plasmonic resonance and coupling

Abstract

A metal-insulator-metal (MIM) structure which is used to enhance the focusing energy of planar lens is developed in this work. The top of the MIM structure is formed by circularly arranged V-shaped nanoantennas whose double resonance effect makes it possible for light to obtain great phase changes within an ultra-thin area. The middle and bottom of the structure is medium and gold film layer respectively. This structure produces plasmonic coupling between the antenna layer and gold film, thus reducing Ohmic loss and enhancing the effect of plasmonic excitation. When the distance between the antenna layer with a thickness of 30 nm and gold film is 88 nm, and the thickness of gold film is 20 nm, the enhancement of plasmonic coupling reaches to the strongest when the focusing intensity is 1.33 times higher than the lens only. With the advantages of small size, ultra-thin, great phase changes and high-efficient focusing ability, the enhanced plasmonic coupling lens structure can be widely applied in photoetching, and integrated optics.

Measurement and analysis of the surface roughness of Ag film used in plasmonic lithography

“…Usually, the silicon and several metals are used as the template substrate and structure materials, [18,19] where the metals can also be used in plasmonic devices. [20,21] In this study, the Ag/PR/Ag structure is examined to demonstrate the effectiveness of the method in measuring the morphology of both sides of the top Ag film. Firstly, the upper side of the stacked film is measured by an atomic force microscope (AFM).…”

Compact and Efficient Ring Resonator–Based Plasmonic Lens with Multiple Functionalities

“…A few unique properties of SPPs such as the ability to go beyond the classical diffraction limit, propagation at the nanoscale, and extraordinary transmission make it possible to manipulate photons at the nanoscale [3][4][5]. Faster and more efficient miniature photonic devices can be realized using these properties which can open up new possibilities in the fields of optoelectronics, material sciences, biophotonics, and nanoscience [6][7][8].…”

“…This same principle of wave shaping is adopted in a variety of SPP-based nanofocusing devices [13][14][15][16][17][18][19][20][21][22][23]. Nano-antenna arrays were also suggested to efficiently focus light [6,12]. A side-illuminated plasmonic planar lens was proposed wherein a set of grooves was used to couple SPP mode propagating in a bus waveguide to free space.…”

Thermally Tunable Infrared Metalens Using Phase Change Material

“…As a two-dimensional planar metamaterial form, metasurfaces are also demonstrated remarkable characteristics in various application areas [7][8][9][10][11][12]. Control and manipulation of the emergent electromagnetic wavefront are one of the signi cant implementations of the metasurfaces in the optical device technologies [13]. The at metasurface lenses called as metalenses are candidates to replace conventional bulky spherical lenses which are one of the obstacles to downsizing the modern optical devices [14].…”