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In this study, we present large enhancement of effective dielectric constant of magnetodielectric metamaterials made from two layers of parallel periodic non-magnetized iron wires embedded inside dielectric (wax), in two orientations of them, relative to the incident electromagnetic field. This kind of enhancement is predicted by finite difference time domain (FDTD) method electromagnetic simulations made for infinite size metamaterials of same unit cell and same electromagnetic wave's geometry of incidence. In this model, the complex internal constants were estimated from the calculated complex S-parameters by using Ross-Nicolson method. The validity of our prediction was tested, from comparison of calculated S-parameters with experimental ones measured on a sample made by rapid prototyping, using a modified strip transmission line method. The dielectric enhancement was found to be about 500%, as it was expected from simulations. Applicability of this family of metamaterials to ferrites like applications is discussed.

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A microstrip slit‐tetragonal resonator gap‐loaded with a piece of silicon is proposed as optical tuning element. Change of photoconductivity of silicon, after irradiation of it with an infrared lamp, results a significant change of density (∼25 dB) of the first resonant peak (n = 1/2) of resonator. This behavior makes this device a possible candidate for optical tuning of microwave transmission lines at specific operating frequency. Measured S‐parameters of the proposed device are in good agreement with simulated ones found from finite difference time domain method. Calculation of S‐parameters based on a transmission line model is included for comparison. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 699–702, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22240

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