IFDDA, an easy-to-use code for simulating the field scattered by 3D inhomogeneous objects in a stratified medium: tutorial

In this tutorial, we introduce a solver of monochromatic Maxwell equations made freely available at https://www.fresnel.fr/perso/chaumet/ifdda.html , based on the volume moment method. The Institut Fresnel Discrete Dipole Approximation or Idiot-Friendly Discrete Dipole Approximation (IFDDA) calculates the diffracted field, the optical forces, and the image through a microscope of any three-dimensional inhomogeneous object, possibly anisotropic, placed in a stratified medium. In this method, only the object is meshed so the required memory space is kept to a minimum. We describe the principle and the potentialities of IFDDA and present comparisons with Mie theory and experimental data to assess the accuracy of the method. In addition, we provide a user guide for first steps with the solver. We hope that you will use and enjoy this numerical tool!