Heidelberg - Jena - Database of Optical Constants (HEJDOC)

Kramers-Kronig (KK) codes:

The integral Kramers-Kronig relations connect the real and imaginary parts of optical constants of a material at a frequency point with their values over the whole frequency domain (see e.g. Bohren & Huffman, 1983)
  1. KK toolbox
    These tools developed by Volker Ossenkopf include an interactive program that allows to check the KK consistency of refractive index or dielectric functions and extrapolate them. Computations are controlled by eye via graphical plots. The code is available here.
  2. KK analysis
    A special part of the KK toolbox for the analysis of transmission spectra of samples. The code is available here.


Effective medium theory (EMT):

The EMT presents an approximation to estimate the optical properties of an inhomogeneous particle by its substitution with a homogeneous particle having an effective refractive index.
  • EMT calculators
    Nice programs created by Volker Ossenkopf. They allow one to find the effective refractive index for some rules of EMT, several kinds of inclusions of different shapes, etc. The codes (emc, nemc) are available here.


    Light scattering codes:

    1. Thomas Wriedt's list of codes
      Many links and references to different scattering codes available are given. An extended section on Mie theory codes includes a lot of simple and not simple codes for homogeneous spheres as well as codes for layered spheres, spheres with non-concentric inclusions, a sphere or cylinder on surface, bispheres. Most of these codes and T-matrix codes for rotationally symmetric scatters are free. In contrast, 3D codes are mainly commercial. They are based on different approaches: generalized multipole technique, method of moments, finite element and other methods. Not only Fortran codes, but some in C++, Pascal, etc.
    2. a Java Mie code
      This code allows you to calculate the optical properties of a homogeneous sphere without leaving Internet.
    3. a couple of other Mie codes
      These codes calculate cross-sections, scattering matrix and (sometimes) the Planck averages for homogeneous spheres (and arbitrary ellipsoids in the quasistatic limit). There is a program to find the cross-sections for the case when the material has the magnetic permeability different from 1. The codes are available here.
    4. a Separation of Variables code
      The code simulates light scattering by homogeneous oblate and prolate spheroids with high accuracy. It provides cross-sections (and scattering matrix elements) for oblate and prolate spheroids in a very wide range of aspect ratio, size, and refractive index values.
    5. a sophisticated T-matrix code
      The code computes the light scattering by rotationally symmetric particles in fixed and random orientations. The code is much faster than any 3D technique (see below). It is in particular efficient when an averaging over particle's orientations is required.
    6. a 3D DDA code
      The standard tool for calculations of light scattering by particles of complex shape, structure, composition, etc. It is not fast when the particle's size is larger than the wavelength of incident radiation.


    • 04.06.2024