Abstracts - Dipartimento di Elettronica Applicata

Meta 2010 & FEM 2010 – Rome, 13-15 December 2010
Parametrical analysis of metamaterials fish-net
Giuseppe Parisi (1,2) , Davide Sammito (2,3) , Marco Natali (4) , Stefano De
Zuani (1,2) , Denis Garoli (1,2,3) and Filippo Romanato (1,2,3)
(1) University of Padova, Department of Physics
Padova, Italy – E-mail: giuseppe.parisi@unipd.it
(2) LaNN, Laboratory for Nanofabrication of Nanodevices
Padova, Italy
(3) IOM-TASC Natl. Lab. CNR-INFM, Trieste, Italy
(4) CNR-ICIS, Padova, Italy
Recently, the fabrication and optimization of nano-hole arrays in noble metal
layers has attracted much attention both because of the interesting new physics
associated with them and for their potential applications in nano-optics and
biosensing [1,2]. Electric tuneability of the negative refractive index
wavelength is theoretically foreseen to be possible by use of dielectrics with
electro-optical properties such as PZT. Here we report a design and a
parametrical analysis of metamaterial fishnet in the optical spectral range [3].
In particular a dependence analysis on the geometric features of the fishnet is
carried out for both the magnetic and the electric resonance. We found out that
a sharp negative resonance (electric in nature) is down-shifted to 200 nm by a
stronger resonance (magnetic in origin). This split the bandwidth of negative
refractive index in two frequency domains. For appropriately designed of
squared hole-array structures, the frequency of the magnetic resonance
coincides with a region of negative effective permittivity and a negative index
of refraction is seen in the simulation. In figure 1 the simulated effective
transmittance, reflectance and absorbance of the proposed structure are shown.
We also show in figure 2 how the electric and magnetic resonance depend by
the squared hole of the fishnet.
Fig. 1. Simulated transmittance, reflectance
and absorbance.
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Fig. 2. Simulated dependence of negative
refractive index on the hole size
References
[1] N.C.Lindquist , A. Lesuffleur, and H.Im Oh, Lab Chip, 9 (2009) 382 - 387.
[2] J. Ji, G. O'Connel, D.J.D. Carter and D.N. Larson, . Anal. Chem., 80 (2008) 2491-2498
[3] J. Valentine, S. Zhang, T.Zentgraf, E. Ulin-Avilal, D.A. Genov, G. Bartal, X. and Zhang,
Nature 455 (2008) 367-379.