Targeted Microwave Heating Induced by Split-Ring Resonator

In this work, we show how localized, small-scale, and targeted heating can be induced in a microwave reaction cavity (MRC) by enhancing the electric field through the split-ring resonator (SRR) at the gap. During excitation of the cavity, an intense electric field is generated in the gap of the SRR, which heats a $4\times 4$ mm hotspot on the sample small enough to realize targeted microwave heating. To validate the results, the experimental system is built, and the corresponding experiments are performed, achieving excellent agreement between simulations and measurements. In addition, the relationship between the temperature of the hot spot and the intensity of the electromagnetic field component at the SRR gap is investigated. Finally, the SRR is moved across the cavity and spatially targeted microwave heating is achieved.