Calibrating quantum hydrodynamic model for noble metals in nanoplasmonics

TL;DR

This paper refines and calibrates a quantum hydrodynamic model for noble metals in nanoplasmonics, enhancing its accuracy for predicting optical responses of nanostructures by benchmarking against density functional theory.

Contribution

The paper introduces a calibrated, refined quantum hydrodynamic model specifically tailored for noble metals in nanoplasmonics, validated through benchmarking with density functional theory.

Findings

Calibrated model accurately predicts optical responses of gold nanomatryoshkas.

Refined QHDM incorporates near-field effects and dielectric properties.

Model enables quasinormal mode analysis for nanostructures.

Abstract

Quantum hydrodynamic model (QHDM) has become a versatile and efficient tool for studying plasmonics at the nanoscopic length scale. Yet its application to noble metals has not been sufficiently justified, in particular for situations where the metallic structures interface with dielectric material and electrons spill over the interfaces. In a recent work, we developed a refined QHDM, where the near-field effects and static polarization of metal ion lattice, and the electron affinity and static permittivity of the dielectric are incorporated. Here we perform a careful calibration of the model parameters for the refined QHDM. The model parameters are determined by benchmarking with (time-dependent) density functional theory calculations for special cases of simple metal. The predictive power of the refined QHDM with calibrated model parameters is faithfully demonstrated by the calculations of the optical responses from gold nanomatryoshkas of different sizes. The refined QHDM approach allows the quasinormal mode analysis for revealing the intrinsic optical properties of the nanoscopic metallic structures. We expect the well-calibrated refined QHDM would provide the nanoplasmonics community with a useful tool.