Abstract
Several converging lenses working in the permittivity near to zero (ENZ) regime at optical frequencies are designed using an array of metal-dielectric-metal plasmonic waveguides. These plasmonic waveguides show a dispersive nature that enable to mimic an effective ENZ medium when using the fast wave transverse electric (TE1) mode near its cut-off wavelength. By arranging multiple plasmonic waveguides with the correct engineered dimensions, several metalenses, including graded index (GRIN) ones, and diffractive optical elements (i.e., zoned metalenses) are proposed. The metalenses are designed at λ0 = 474.9nm (f = 631.67THz) with a focal length of 10.75λ0. Numerical results demonstrate that the best performance is obtained for the case of the GRIN metalens in terms of the focal position, transversal resolution and thickness, reducing its volume up to ~52.3% with respect to the smooth-profiled plano-concave metalens.
Original language | English |
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Pages (from-to) | 162-168 |
Number of pages | 7 |
Journal | Optics & Laser Technology |
Volume | 80 |
Early online date | 19 Jan 2016 |
DOIs | |
Publication status | Published - Jun 2016 |
Keywords
- ENZ artificial materials
- Optical focusing
- Focusing
- Metamaterials
- Lenses
ASJC Scopus subject areas
- Condensed Matter Physics
- Electrical and Electronic Engineering