Computation of Optical Force on Nanoparticles Using Locally Non-Orthogonal Overlapping Yee FDTD Method

Jinjie Liu,Jerome V Moloney,Moysey Brio

doi:10.4236/jemaa.2012.411063

Jinjie Liu, Jerome V Moloney + Show 1 more

Open Access

https://doi.org/10.4236/jemaa.2012.411063

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Abstract

In this paper, a locally non-orthogonal overlapping Yee (OY) FDTD method is proposed in order to accurately calculates the optical force on dielectric and dispersive nanoparticles. It extends our previous work to geometries with sharp corners and dispersive materials. In addition to consistently achieving the smallest errors in comparison to the standard FDTD method, the OY approach is a stable non-orthogonal FDTD method that attains second-order convergence when sharp corners are present.

Highlights

Recent advances in optical trapping of nanoparticles, originated by Ashkin [1,2], have been successfully applied in both physics and biology [3]
A locally non-orthogonal overlapping Yee (OY) finite-difference time-domain (FDTD) method is proposed in order to accurately calculates the optical force on dielectric and dispersive nanoparticles
The subpixel smoothing technique proposed in [16] achieves second-order accuracy by using an inverse dielectric tensor, and this method has been extended to anisotropic media [17], combined with a recently proposed stable FDTD scheme in anisotropic media [18]

Summary

Introduction

Recent advances in optical trapping of nanoparticles, originated by Ashkin [1,2], have been successfully applied in both physics and biology [3]. The subpixel smoothing technique proposed in [16] achieves second-order accuracy by using an inverse dielectric tensor, and this method has been extended to anisotropic media [17], combined with a recently proposed stable FDTD scheme in anisotropic media [18] As it has been pointed out in [16], a remaining challenge is to accurately handle objects with sharp corners, where the accuracy is still less than second-order. Numerical simulations on optical force computation confirm that in addition to consistently achieving the smallest errors in comparison to the standard FDTD method, the new approach is stable and attains second-order convergence when sharp corners are present

The Locally Non-Orthogonal OY Algorithm t

Numerical Simulations

Findings

Conclusion