A compact meta‐atom for dual band negative permittivity metamaterial

Abstract

In this letter, a compact design of electric meta‐atom has been proposed as a dual band negative permittivity metamaterial. Compared with the earlier work, the proposed dual band meta‐atom has a better coupling strength at both the resonances and it is also more compact. This dual band design utilizes the mechanism of the resonance coupling between a meander line loaded delta loop meta‐atom and a rectangular close ring meta‐atom. The proposed meta‐atom is designed and investigated by both simulation and experiment with good agreement. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1152–1156, 2015

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

“…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 open delta loop resonator (ODLR) proposed by Sabah [30] is shown to have single-band magnetic response for parallelly incident wave, whereas Sarkhel [26] has recently shown electric response for meander-line loaded closed delta loop resonator (CDLR) for normally incident wave. However disadvantage of both designs is that they are highly polarization sensitive.…”

“…For comparison, we have considered unit cells operating in microwave regime. From Table 3, it is indicated that, compared to [17,18,20,26], the proposed TBEMR structure exhibits triple-band response and highest value of ( 0 / ) ratio at lower resonant frequency of 4.32 GHz. Moreover at other two resonant frequencies, its value more than 4 is maintained.…”

“…In recent years, research in this particular area includes electrical size reduction, improvement in effective medium ratio [23], and achieving dual-band characteristics [24][25][26]. Size reduction is achieved by a common idea of raising overall inductance and capacitance in the unit cell, thus achieving lower resonant frequency.…”

“…However, above approaches have limitations due to difficulty and complexity in the fabrication and cost and availability of high permittivity substrates. The dual-band characteristic is obtained by combining different resonating structures and optimizing them to get response in desired frequency band [24][25][26]. A pair of E-LCs resonators with different sized inductive loops and capacitive gaps were shown to have two distinct electric resonances [24,25].…”

“…However, shortfalls in these designs are poor coupling to external field at higher resonant frequency [24] and use of high permittivity material as substrate [25]. A dualband negative permittivity metamaterial design based on integration of the delta loop within closed square ring resonator was proposed in [26]. However, meander loaded delta increases complexity of the design.…”