Full Hydrodynamic Model of Nonlinear Electromagnetic Response in Metallic Metamaterials

TL;DR

This paper introduces a finite-difference time-domain (FDTD) hydrodynamic model for metallic metamaterials that captures nonlocal and nonlinear electromagnetic interactions, enabling advanced analysis and design of nonlinear nanodevices.

Contribution

It develops a self-consistent FDTD hydrodynamic model that incorporates nonlocal and nonlinear effects in metallic metamaterials, extending beyond traditional local-linear responses.

Findings

Demonstrates charge, energy, and angular momentum conservation in high-order harmonic generation

Provides nonlinear optical response simulations for complex metallic metamaterials

Enables characterization and design of nonlinear nanodevices

Abstract

Applications of metallic metamaterials have generated significant interest in recent years. Electromagnetic behavior of metamaterials in the optical range is usually characterized by a local-linear response. In this article, we develop a finite-difference time-domain (FDTD) solution of the hydrodynamic model that describes a free electron gas in metals. Extending beyond the local-linear response, the hydrodynamic model enables numerical investigation of nonlocal and nonlinear interactions between electromagnetic waves and metallic metamaterials. By explicitly imposing the current continuity constraint, the proposed model is solved in a self-consistent manner. Charge, energy and angular momentum conservation laws of high-order harmonic generation have been demonstrated for the first time by the Maxwell-hydrodynamic FDTD model. The model yields nonlinear optical responses for complex metallic metamaterials irradiated by a variety of waveforms. Consequently, the multiphysics model opens up unique opportunities for characterizing and designing nonlinear nanodevices.