Abstracts - Dipartimento di Elettronica Applicata

Meta 2010 & FEM 2010 – Rome, 13-15 December 2010
Tunable metamaterials operating
in the terahertz region
Nassim Chikhi (1) , , Emiliano Di Gennaro (1) , Antonello Andreone (1) , Emanuela
Esposito (2) , Ilaria Gallina (3) , Giuseppe Castaldi (3) , and Vincenzo Galdi (3)
(1)
CNR-SPIN and University of Naples “Federico II,” Department of Physics
Naples, Italy – E-mail: chikhi@na.infn.it, emiliano@na.infn.it, andreone@unina.it
(2)
CNR-ICIB “E. Caianiello”,
Pozzuoli (Na), Naples, Italy – E-mail: e.esposito@cib.na.cnr.it
(3)
University of Sannio, Department of Engineering
Benevento, Italy – E-mail: ilaria.gallina@unisannio.it, castaldi@unisannio.it,
vgaldi@unisannio.it
During the last two decades, substantial progress has been achieved in the
development of terahertz (THz) science and technology. However, there are several
restrictions which limit the development of fruitful applications within the full THz
frequency region. One of the main constraints is the lack of appropriate responses, at
those frequencies, from many naturally existing materials. This problem can be solved
using artificially structured electromagnetic materials (“metamaterials”), typically
comprised of periodic arrays of sub-wavelength metallic resonating inclusions.
Different strategies have been explored in order to achieve tunability in the resonating
inclusions within various ranges of frequencies, from microwaves to the THz region,
including the use of different kinds of capacitors, microelectromechanical systems
(MEMS) or liquid crystals [1-3]. The geometry that we considered here is based on
the concept of split ring resonator (SRR) [4, 5]. A comprehensive numerical study
based on full-wave simulations (via CST Microwave Studio ) has been carried out
in order to characterize the device response in the required frequency region. The
proposed tuning mechanism is based on the use of a liquid crystal (LC).
References
[1] S. Gevorgian, and A. Vorobiev, “Tunable metamaterials based on ferroelectric varactors”,
Proceedings of the 37 th European Microwave Conference, 2007 EuMA, Munich, Germany.
[2] T. Hand and S. Cummer, “Characterization of tunable metamaterial elements using MEMS
switches”, IEEE Antennas Wireless Propag. Lett. 6, 401 (2007).
[3] J. A. Bossard, et al., “Tunable frequency selective surfaces and negative-zero-positive index
metamaterials based on liquid crystals”, IEEE Trans. Antennas Propag. 56, 1308 (2008).
[4] H. Chen, et al., ”Experimental demonstration of frequency-agile terahertz metamaterials”, Nature
Phot. 2, 295 (2008).
[5] K. Aydin, and E. Ozbay, “Capacitor-loaded split ring resonators as tunable metamaterial
components”, J. Appl. Phys. 101, 024911 (2007).
[6] F. Zhang, L. Kang, Q. Zhao, J. Zhou, X. Zhao, and D. Lippens, ”Magnetically tunable left handed
metamaterials by liquid crystal orientation”, Optics Express 17, 4360 (2009).
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