Abstracts - Dipartimento di Elettronica Applicata

Meta 2010 & FEM 2010 – Rome, 13-15 December 2010
Effect of Localized States on Photonic
Quasicrystal Waveguides
Emiliano Di Gennaro (1) , Priya Rose T. (1) , Gianluigi Zito (2) , Giancarlo
Abbate (1) , and Antonello Andreone (1)
(1) CNR-SPIN and University of Naples “Federico II,” Department of Physics
Naples, Italy – E-mail: emiliano@na.infn.it, priyarose@na.infn.it,
abbate@na.infn.it, andreone@unina.it
(2) CNR-ICIB “E. Caianiello”,
Pozzuoli (NA), Italy – E-mail: zito.gianluigi@libero.it
In recent years, photonic quasicrystals have attracted enormous interest in the
field of photonics of complex structured materials. The lack of translational
symmetry into quasiperiodic and aperiodic crystals is compensated by longrange
quasiperiodic translational order and high rotational symmetries not
achievable by conventional periodic crystals. Photonic Quasicrystals (PQCs)
may possess large photonic bandgaps (PBGs) [1,2] with very interesting
properties of light transmission, wave guiding and localization [3] that can be
exploited in a wide variety of electro-optical and photonic applications.
In this work we study the PBG properties of an octagonal interferential PQC.
The 2D quasiperiodic pattern is obtained by placing ideal dielectric cylinders
(infinitely long) where the interference of 8 coherent light beams shows its
local maxima [4]. In order to characterize the in-plane PBG properties of the
abovementioned structure, we have designed and performed a series of
experiments in the microwave regime (8-20 GHz). The sample under study
consists of alumina cylindrical rods in air inserted in a parallel plate
waveguide. Transmittance and field maps are obtained using an x-y robot and
two dipole antennas connected to a two-port vectorial network analyzer
(VNA) HP 8720C [5]. We focus on the response of a linear waveguide,
whose transmittance can be controlled by tuning the dielectric properties of
the central post. Experimental results are compared and found in very good
agreement with numerical simulations obtained by finite differences timedomain
technique.
References
[1] M.E. Zoorob , M.D.B. Charlton, G.J. Parker, J.J. Baumberg, M.C. Netti, “Complete
photonic bandgaps in twelve-fold symmetric quasicrystals” Nature 404, 740, 2000
[2] Y. S. Chan, C. T. Chan, and Z. Y. Liu, “Photonic Band Gaps in Two Dimensional
Photonic Quasicrystals” , Phys. Rev. Lett. 80, 956, 1998
[3] S. S. M. Cheng, L. Li, C. T. Chan, and Z. Q. Zhang, "Defect and transmission properties
of two-dimensional quasiperiodic photonic band-gap systems," Phys. Rev. B 59, 4091,
1999
[4] G. Zito, B. Piccirillo, E. Santamato, A. Marino, V. Tkachenko, and G. Abbate, "Twodimensional
photonic quasicrystals by single beam computer-generated holography," Opt.
Express 16, 5164, 2008
[5] E. Di Gennaro, C. Miletto, S. Savo, A. Andreone, D. Morello, V. Galdi, G. Castaldi, and
V. Pierro, “Evidence of local effects in anomalous refraction and focusing properties of
dodecagonal photonic quasicrystals,” Phys. Rev. B 77, 193104, 2008
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