Quantum mechanical study of plasmonic coupling in sodium nanoring dimers

Quantum Plasmonics: Optical Properties of a Nanomatryushka

“…The plasmon resonances, which are highly dependent on both chemical composition and geometry, can be tuned to wavelengths spanning the visible and near-infrared regions of the electromagnetic spectrum. Examples of nanostructures that have demonstrated plasmon tunability and significant field enhancements include spherical core–shell particles such as nanoshells, , nanorods, − nanorings, − and nanoparticle dimers. − …”

Understanding Quantum Plasmonics from Time-Dependent Orbital-Free Density Functional Theory

“…On this regard, time-dependent density functional theory (TDDFT) has been very successful and widely used to capture electron tunneling and screening across the nano-junctions and to yield finite field enhancements at the interfaces. 47,49,[53][54][55][56][57][58][59] Unfortunately, TDDFT calculations are computationally demanding for even moderately sized plasmonic systems, and as a result, previous TDDFT works have been confined to small nanoparticle dimers. 54,55,[57][58][59] More importantly, many TDDFT calculations have been performed in conjunction with jellium model 46,47,49,53,56,60,61 in order to reduce the computational cost.…”

“…To rectify the problems, quantum mechanical approaches that fully account for nonlinear and nonlocal effects are essential and can completely change the spectral distribution and the field enhancements predicted by the classical theories. − There are some recent theoretical efforts to incorporate quantum effects into the classical theories, including the quantum corrected model, ,, the projected dipole layer model, , and the extended hydrodynamic model. , Notwithstanding their usefulness, fully quantum mechanical descriptions based on explicit treatment of ground- and excited-state charge densities are highly desirable and in fact often necessary for reliable predictions. On this regard, time-dependent density functional theory (TDDFT) has been very successful and widely used to capture electron tunneling and screening across the nanojunctions and to yield finite field enhancements at the interfaces. ,,− Unfortunately, TDDFT calculations are computationally demanding for even moderately sized plasmonic systems, and as a result, previous TDDFT works have been confined to small nanoparticle dimers. ,,− More importantly, many TDDFT calculations have been performed in conjunction with jellium model ,,,,,, in order to reduce the computational cost. In the jellium model, the ionic charge density of a nanoparticle is assumed to be uniform, terminating at the nanoparticle surface.…”