Experimental realization of plasmonic filters for multispectral and dual-polarization optical detection

摘要

We report the design and implementation of a new class of plasmonic filters that are both wavelength and polarization selective. The plasmonic filter consists of a five-layer metallic photonic crystal structure and operates inside the photonic bandgap regime. We show that by manipulating the middle layer geometry alone, it is possible to tune the Fabry–Perot resonance over a broad spectral range ( λ = 1.25 to 1.63   μ m ) and in a monolithic fashion. Furthermore, we show that the resonance has a definite polarization character that is determined by the orientation of the first layer grating. The plasmonic filter may be integrated with an array of photodetectors for high-throughput spectral and polarimetric imaging applications.