Double Fano resonances of cylindrical metastructures in X-band based on intercomponent coupling and wave interaction

The property of the metal cylinder system is demonstrated experimentally. Cylindrical dimers and trimers made of 99% copper have been studied, a double Fano resonance has been observed and quality-factor exceeded 300. The magnetic field in the near field region was observed using a thermoelastic optical indicator microscope (TEOIM), and its interaction with the waves in the transition zone was observed through the waveguide on the vector network analyzer (VNA). Thus, it became clear that Fano resonances in trimers have a different physical nature. The first of them, observed at 9.05 GHz, is the result of the interaction of the wave and the whole system, which was also observed in dimers. The second resonance is sharper and was observed at 9.47 GHz, resulting from interrod coupling. Due to its simplicity and controllability, the system can be very attractive for fabricating sensors and other frequency-selective devices in the microwave range.