In this work, we propose a plasmonic absorber structure composed of periodic gratings with hexagonal arrangements aided by rectangular metal-dielectric layers and PCM's (Phase Change Materials) in the infrared spectrum, between 1200-6000 nm, which has high optical contrast in these regions, thus favoring its use. The transition effects between the intermediate to amorphous and crystalline phases of the PCMs layers are analyzed, based on the LorentzLorenz relationship. Absorption effects can be controlled using functions in which geometric parameters and crystallization levels can be related. The results presented show high absorption above 95% in both phases of the material, in normal incidence. The physical mechanisms of absorption confinement were also investigated. These structures can offer great light coupling advantage in reconfigurable nanoplasmonic devices.
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