In this work, led by Group of Magnetic Nanomaterials, we present a comprehensive study of the plasmonic resonances in an inverted honeycomb lattice through a combination of numerical simulations and EELS measurements. The high quality of the fabricated samples, together with the outstanding spectral and spatial resolution of the EELS measurements has allowed the mapping of several bright and dark plasmonic modes. Among the dark modes detected, it is especially remarkable the finding of modes that consist in the antiferroelectric arrangement of the charges surrounding the slits that form the lattice. Such a charge configuration lets us classify the slits in two different sublattices that exhibit a unit cell two times larger than that of the original lattice.
Imaging of Antiferroelectric Dark Modes in an Inverted Plasmonic Lattice. J. Rodríguez-Álvarez, A. Labarta, J. Carlos Idrobo, R. Dell’Anna, A. Cian, D. Giubertoni, X. Borrisé, A. Guerrero, F. Perez-Murano, A. Fraile Rodríguez, and X. Batlle. ACS Nano, 2023