A Subwavelength Microstrip Resonator Based on Metamaterials

A metamaterial-based subwavelength microstrip resonator with high quality factor and simple fabrication process was proposed. For the experimental result, a quality factor of about 70 was achieved when the length of the resonator was about one third of the wavelength. Firstly, the mu-negative metamaterial (MNM) and the epsilon-negative metamaterial (ENM) were implemented by loading only chip capacitors or only chip inductors onto the microstrip. The implementation process is simpler in comparison to the traditional implementation method of the MNM and the ENM based on the microstrip. Then, the transmission characteristics of the heterostructure constructed of the MNM and the ENM fabricated through the simple method were investigated and the results showed that a subwavelength microstrip resonator could be built by the MNM–ENM heterostructure. Moreover, the quality-factor enhancement of the subwavelength microstrip resonator based on the MNM–ENM heterostructure was also explored. The results showed that the quality factor could be notably boosted and increased by about 15 times for the experimental result of the sample owing to more intensive confinement of the electromagnetic field when the electromagnetically induced transparency-like metamaterial was introduced at the interface of the MNM–ENM heterostructure.