Novel High-Sensitivity Racetrack Surface Plasmon Resonance Sensor Modified by Graphene

In order to overcome the existing challenges presented by conventional sensors, including their large size, a complicated preparation process, and difficulties filling the sensing media, a novel high-sensitivity plasmonic resonator sensor which is composed of two graphene-modified straight waveguides, two metallic layers, and a racetrack nanodisk resonator is proposed in this study. The transmission characteristics, which were calculated by the finite element theory, were used to further analyze the sensing properties. The results of quantitative analysis show that the proposed plasmonic sensor generates two resonance peaks for the different incident wavelengths, and both resonance peaks can be tuned by temperature. In addition, after optimizing the structural parameters of the resonator, the Q value and the refractive sensitivity reached 21.5 and 1666.67 nmRIU(−1), respectively. Compared with other studies, these values translate to a better performance. Furthermore, a temperature sensitivity of 2.33 nm/5 °C was achieved, which allows the sensor to be easily applied to practical detection. The results of this study can broaden the useful range for a nanometer-scale temperature sensor with ultrafast real-time detection and resistance to electromagnetic interference.