Simultaneous Functionality of Tamm Plasmon Mode-Based Refractive Index Sensor Across Multiple Photonic Bandgaps

Abstract In this work, a refractive index sensor based on Tamm plasmons mode is proposed, capable of concurrent functionality across diverse photonic bandgaps. The proposed sensor structure consists of an analyte cavity sandwiched between a one-dimensional photonic crystal of SiO2/TiO2 and a thin metal film. Tamm resonances are observed within different photonic bandgaps. The functioning principle of this optical sensor relies on altering the refractive index of the analyte, resulting in a shift in either the transmission or reflection spectrum. The study reveals that the resonance wavelength demonstrates a linear increase with the rise in the analyte's refractive index. The study reveals that simultaneous utilization of Tamm Plasmon sensors across multiple bandgaps enables multiplexed sensing, where we can detect multiple analytes or parameters in parallel. Tamm resonance-based sensors, notable for their main advantage of prism-free coupling, offer a compelling alternative to other optical sensors like surface plasmon resonance-based sensors.