Numerical Modeling of a Nanostructure Gas Sensor Based on Plasmonic Effect

In the present paper, a nanostructure plasmonic gas sensor based on ring resonator structure at the wavelength range of 0.6-0.9 μm is presented. The plasmonic materials/SiO2 with the advantage of high mobility and low loss is utilized as a substrate for structure to obtain some appropriate characteristics for the sensing Performance parameters. To evaluate the proposed sensor and calculation of performance parameters including figure of merit and sensitivity, the effect of the different gas including Carbon Dioxide (CO2), Acetonitrile (C2H3N), Carbon disulfide, and Sarin are considered. For this purpose 3D-FDTD method is considered. Our calculations show that by coupling between the incident waves and the surface plasmons of the structure, a high transmission ratio of 0.8 and relatively low insertion loss of 6 dB around the wavelength interval of 0.6-0.9 μm are achievable. Furthermore, the calculated sensitivity and figure of merit are 28 and 8.75, respectively. This provides a path for development of nanoscale practical on-chip applications such as plasmonic memory devices.