SPECTRAL-TEMPORAL DYNAMICS OF TRANSIENT ABSORPTION OF MULTILAYER PERIODIC PLASMONIC NANOSTRUCTURES

Abstract

The features of the induced changes in the optical density spectra of multilayer Ag-Na₃ AlF₆ nanostructures under a femtosecond laser pulses exitation in the band of surface plasmonic resonance of absorption (SPRA) were studied. The dependence of the amplitude of the induced changes on the thickness of the dielectric Na₃ AlF₆ films separating the monolayeres of silver nanoparticles was registered. A significant increase of the optical response amplitude (up to 80 %) was found for the nanostructures with the quarter-wavelength Na₃ AlF₆ interlayers. For nanostructures with different-thickness dielectric Na₃ AlF₆ interlayers the characteristic relaxation times of induced changes at an excitation energy of 5–10 μJ do not practically vary, are equal to ~2 ps and coincide with the kinetic response time parameters of the used silver nanoparticle monolayers.