A first-principles simulation method for ultra-fast nano-optics

Mitsuharu Uemoto,Shunsuke A Sato,Taisuke Boku,Kazuhiro Yabana,Yuta Hirokawa

doi:10.1051/epjconf/201920504023

Abstract

We develop a computational approach for ultrafast nano-optics based on first-principles time-dependent density functional theory. Solving Maxwell equations for light propagation and time-dependent Kohn-Sham equation for electron dynamics simultaneously, intense and ultrashort laser pulse interaction with a dielectric nano-structure is described taking full account of nonlinear effects. As an illustrative example, irradiation of a pulsed light on silicon nano-sphere system is presented.

Highlights

Computational approaches solving Maxwell equations have been recognized as basic and indispensable tools in wide areas of optical science
We develop a theoretical and computational method of electron dynamics based on timedependent density functional theory (TDDFT)
We describe our recent attempt to extend our approach to ultrafast threedimensional (3D) nano-optics, solving 3D-Maxwell and 3D-time-dependent Kohn-Sham (TDKS) equations simultaneously

Summary

Introduction

Computational approaches solving Maxwell equations have been recognized as basic and indispensable tools in wide areas of optical science. We develop a theoretical and computational method of electron dynamics based on timedependent density functional theory (TDDFT). We invented a computational method to solve the time-dependent Kohn-Sham (TDKS) equation, a basic equation of the TDDFT, in real time and real space [1]. We further combine microscopic electron dynamics calculations with macroscopic Maxwell equations that describe light-wave propagation using a multiscale strategy [2]. We applied the method to ultrafast electron dynamics in dielectrics induced by few-cycle femtosecond laser pulses [3,4]. We describe our recent attempt to extend our approach to ultrafast threedimensional (3D) nano-optics, solving 3D-Maxwell and 3D-TDKS equations simultaneously. We first describe the formalism and present, as an illustrative example, a calculation of an intense and ultrashort laser pulse interaction with a layered material composed of silicon nano-spheres

Formalism

Application to Silicon Nano-sphere