Plasmon Hybridization in Rotation Bimetallic-Chain System

Plasmon hybridization phenomena in metallic chain heterodimers represent a frontier in nanoscale optoelectronic research, offering insights into the quantum mechanisms that govern their behavior. Utilizing first-principles-based computational methods, we conduct a systematic study into the dimer configurations formed by Na₈ and Mg₈ chains, encompassing Na₈ homodimer, Mg₈ homodimer, and Na₈Mg₈ heterodimer. The study reveals that with the variation of bichain rotation angles, the plasmonic resonance modes within the dimers undergo significant hybridization, resulting in the emergence of new split peaks at the lower-energy range due to hybridization of the longitude mode and the transverse mode in the middle of the chain induced by it. At the high-energy range, the longitude multipole mode on the other chain is induced by the transverse center, and the interaction results in the splitting and appearance of hidden modes as the rotation angle increases. Both the excitation in the orthogonal direction and the electromagnetic field enhancement effects confirm the hybridization, which also provides the tenability of the plasmon resonance. This research provides a new theoretical perspective for understanding plasmonic hybridization phenomena at the nanoscale and offers important theoretical guidance for designing novel optoelectronic devices based on molecular plasmonics.