Passive Infrared Sensing Using Plasmonic Resonant Dust Particles

Figure 4

Simulation results, using the RCW method, that present the reflectance at normal incidence within the LWIR band as the ZnSe substrate thickness is varied from 1.5 to 2.5 μm. For this simulation, the grating period is fixed at 3.0 μm with a 50% duty cycle. The incident wave was normally incident with parallel polarization. As the substrate thickness is increased, the resonant absorption peak shifts to longer wavelengths but still remains strong. The bandwidth of the resonance also remains relatively fixed as the substrate thicknesses is varied.