pyGDM-A python toolkit for full-field electro-dynamical simulations and evolutionary optimization of nanostructures

pyGDM is a python toolkit for electro-dynamical simulations in nano-optics based on the Green Dyadic Method (GDM). In contrast to most other coupled-dipole codes, pyGDM uses a generalized propagator, which allows to cost-efficiently solve large monochromatic problems such as polarization-resolved calculations or raster-scan simulations with a focused beam or a quantum-emitter probe. A further peculiarity of this software is the possibility to very easily solve 3D problems including a dielectric or metallic substrate. Furthermore, pyGDM includes tools to easily derive several physical quantities such as far-field patterns, extinction and scattering cross-section, the electric and magnetic near-field in the vicinity of the structure, the decay rate of quantum emitters and the LDOS or the heat deposited inside a nanoparticle. Finally, pyGDM provides a toolkit for efficient evolutionary optimization of nanoparticle geometries in order to maximize (or minimize) optical properties such as a scattering at selected resonance wavelengths. Program summary Program Title: pyGDM Program Files doi: http://dx.doi.org/10.17632/8wjcccv73j.1 Licensing provisions: GPLv3 Programming language: python, fortran Nature of problem: Full-field electrodynamical simulations of photonic nanostructures. This includes problems like optical scattering, the calculation of the near-field distribution or the interaction of quantum emitters with nanostructures. The program includes a module for automated evolutionary optimization of nanostructure geometries with respect to a specific optical response. Solution method: The optical response of photonic nanostructures is calculated using field susceptibilities (Green Dyadic Method) via a volume discretization. The approach is formally very similar to the coupled dipole approximation. Additional comments including restrictions and unusual features: Only 3D nanostructures. The volume discretization is limited to about 10000 meshpoints. (C) 2018 Elsevier B.V. All rights reserved.