Extreme subwavelength electric GHz metamaterials

Abstract

We investigate GHz metamaterial resonator arrays that respond to only the electric field with the goal of reducing the resonator size in comparison to the excitation wavelength. By exploiting capactive coupling between the "electrodes" of adjacent resonators, we achieve a large effective capacitance and strong coupling to the applied electric field. By adding meander lines to connect the electrodes, we are able to lower the resonant frequency to obtain a ratio of wavelength to resonator size of about 30. In contrast to other low-frequency designs, our designs do not require vias and maintain strong coupling to the applied field.

Ultra-Compact Metamaterial Absorber With Low-Permittivity Dielectric Substrate

“…We first add meander lines within the resonators while keep the outer ring size fixed to decrease the operating frequency of the MA (equivalent to reduce the electric size for a given frequency). The meander lines technique has been widely used in the engineer area for reducing the electric size of antennas or microwave circuit components, as well as reducing the electric size of metamaterial units [32,33]. Here we gradually add the meander lines to see the decreases of the absorbing frequency.…”

A Compact Triple-Band Negative Permittivity Metamaterial for C, X-Band Applications

“…We started with square loop resonator that already appeared in the literature [19]. The square loop resonator that couples strongly to electric component of electromagnetic wave is widely used for getting -negative response for normal wave incidence as shown in [19,29]. Although square loop resonator has advantage in terms of polarization insensitive behaviour for normally incident wave [29], the disadvantage is regarding single-band response and electrically large size as indicated by very high value of 0 / .…”

“…The geometry of proposed resonator is described in Figure 1 together with design parameters and incident electromagnetic wave excitation. We started with square loop resonator that already appeared in the literature [19]. The square loop resonator that couples strongly to electric component of electromagnetic wave is widely used for getting -negative response for normal wave incidence as shown in [19,29].…”

“…However, these advantages were achieved at the cost of reduced coupling to the external field as indicated by low value (−15 dB) of transmission minima. Kolb et al [19] proposed other notable low resonant frequency structures derived from E-LC resonator for further improvement in 0 / ratio. These structures were inspired from original E-LC resonator.…”

Extremely Sub-Wavelength Negative Index Metamaterial

“…A deeply sub-wavelength electric metamaterial has also been shown operating at GHz frequencies with the ratio of free space wavelength to unit cell size (i.e., referred to as λ 0 /a ratio, where a is the unit cell size in the propagation direction) of about 70 [50]. Deeply sub-wavelength negative index metamaterials have been previously designed based on a lumped element with the unit cell size of only ∼ λ 0 /75 at 400 MHz [51].…”