A Multiscale Method for Optical Responses of Nanostructures

Abstract

We introduce a new framework for the multiphysical modeling and multiscale computation of nano-optical responses. The semiclassical theory treats the evolution of the electromagnetic field and the motion of the charged particles self-consistently by coupling Maxwell equations with quantum mechanics. To overcome the numerical challenge of solving the high-dimensional many-body Schrodinger equations involved, we adopt the time-dependent current density functional theory. In the regime of linear responses, this leads to a linear system of equations determining the electromagnetic field as well as the current and electron densities simultaneously. A self-consistent multiscale method is proposed to deal with the well-separated space scales. Numerical examples are presented to illustrate the resonant condition.