Computational optimization of multi-material layered nanodimer for multipurpose applications in nanotechnology

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2023-12, Vol.129 (12), Article 871
• Main Authors: Jamil, Saqib, Khalil, Usman Khan, Jamil, Saima, Farooq, Waqas
• Format: Article
• Language: English
• Subjects: Applied physics; Asymmetry; Broken symmetry; Characterization and Evaluation of Materials; Charge distribution; Condensed Matter Physics; Dimers; Dipole moments; Gold; Machines; Manufacturing; Materials science; Multilayers; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Plasmonics; Plasmons; Processes; Silicon dioxide; Silver; Surface charge; Surfaces and Interfaces; Symmetry; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-023-07144-5

In this paper, we use computational methods to investigate the plasmonic properties of multi-layered dimers. These dimers are composed of layers of gold–silica–gold and gold–silica–silver, with shifts in their core and middle layers. This asymmetry breaks the geometrical symmetry, revealing plasmon resonances that are typically invisible in concentric geometries. This study explains the origin of these resonances using plasmon hybridization theory, highlighting the interaction between primitive and multipolar modes in the core and shell of the investigated proposed structure. These interactions improve the coupling of the higher order modes to light by inducing a dipole moment. The asymmetry is attributed to the uneven distribution of surface charges, leading to a transition from multipolar to dipolar characteristics in the higher order modes. Through visual examination of the dipolar component in surface charge distributions, we qualitatively establish the relative amplitudes of the modes. Our results demonstrate the red-shifting of resonant wavelengths with increased core offset, resulted in the enhanced absorption rather than scattering. This computational study provide a terse depth for the deeper understanding towards the plasmonic behavior in multilayered dimers with core and middle layer shifts, uncovering the underlying mechanisms of symmetry breaking.