Thomas, S.Singh, M.Satyanarayan, M.N.2026-02-042022IEEE Sensors Journal, 2022, 22, 16, pp. 15916-159221530437Xhttps://doi.org/10.1109/JSEN.2022.3188512https://idr.nitk.ac.in/handle/123456789/22452A high sensitivity refractive index semiconductor-insulator-semiconductor (SIS) waveguide with a ring resonator sensor at THz frequency is proposed. The topological study of the proposed filter is numerically simulated using the finite element method. A maximum sensitivity of 0.509 THz/ Refractive index unit (RIU) is obtained by filling the air-filled ring resonator cavity with different refractive index materials. Besides that, the transmission characteristics are studied by varying the structural dimensions and observed that the system can be treated as a frequency selective device. The device gets modified by incorporating another concentric ring inside the single ring. From the transmission characteristics, the multiple modes of the concentric dual ring are studied, and concluded that the even TM1 mode shows a better response towards frequency tuning. © 2001-2012 IEEE.Finite element methodIII-V semiconductorsIndium phosphideNatural frequenciesOptical resonatorsOptical waveguidesPlasmonicsRefractometersRing gagesSemiconducting indiumSemiconducting indium gallium arsenideSemiconducting indium phosphideConcentric dual ringDual-ringElectromagnetic waveguidesHigh sensitivityRefractive index sensorRing resonatorSemiconductor-insulator-semiconductorSensitivityTerahertz frequenciesTransmission characteristicsRefractive index