We present a comprehensive study of the elementary dipolar contributions to the absorption and scattering cross sections in chiral, twisted, vertically stacked plasmonic plates that have been proposed as acoustoplasmonic transducers. Using a very basic model system we show scattering and absorption cross sections presenting very large qualitative differences for left-circular and right-circular polarizations. We make use of an expansion in vector-spherical-harmonics multipoles to analyze the different contributions to the cross sections depending on the helicity of the incoming wave. In the analysis of the scattering cross section, we demonstrate that interactions not only modify the spectral dependence of the dipoles representing the elements in the nanostructure, but they affect the cross section itself elucidating the dependence on the helicity of the incoming light beam.

A. G.-M. and B. C. L.d.L. acknowledge financial support from the Spanish Ministry of Science and Innovation (MCIN), AEI and FEDER (UE) through projects PID2022-137569NB-C41 (Lightcompass) and TED2021-131417B-I00 (Bigplan-6G). N.D.L.-K. acknowledges funding from the European Research Council Consolidator Grant No.101045089 (T-Recs).

Peer reviewed