Porous Tamm Plasmon based refractive index gas sensor using four different Plasmon active metals

In this work, a multilayer 1D-photonic crystal made with alternating porous silicon materials (PSi1 and PSi2) is used to realize a distributed Bragg reflector where a thin Plasmon active metal layer can be deposited on the top to excite Tamm Plasmon Polaritons. Based on the realization of the Tamm plasmon, a gas sensor capable of detecting change in refractive index of gas sample was designed with a cavity layer (where the maximum intensity of the field took place) in between the metal and the distributed Bragg reflector structure. A comparative analysis has been performed by considering Tamm Plasmon Polaritons excitation using four different Plasmon active metals namely Ag, Au, Al and Pt. We also investigate different performance characteristics of the sensor as a function of different number of pairs constituting the DBR. Our investigation reveals that relevant performance characteristics of the sensor was found to be maximum for Tamm Plasmon Polaritons excitation using Ag. Additionally, the optimum value of number of pairs of alternating porous silicon layers for best performance was found to be N=8 pairs. The proposed sensor is based on a very simple structure and with the choice of appropriate metal layer, the device would be an effective choice for biosensing applications in coming days.