Project 6

Structural and optical properties of dielectric layers

  • Institute: Laser Zentrum Hannover e.V.
  • Principle Investigators: Prof. Detlev Ristau, Dr. Marco Jupé
  • Researcher: Dr. Holger Badorreck

Within the scope of the subproject TP6, the composition of a multiscale model is planned, which allows for a direct correlation of optical and electronic thin film properties with the underlying parameters of the manufacturing process. For this purpose, the resulting material properties can be directly attributed to the layer formation process. In this way the fundamentals are developed for re-classifying and optimizing the coating process. Generally, the description of the full coating process demands for a wide variety of combined simulation techniques. The thin film growth is modeled using classical molecular dynamics (MD), and the resulting structures form the starting point for the calculation of the electronic and optical properties which are extracted applying quantum mechanical methods based on the density functional theory (DFT). Additionally the electronic properties of the material are implemented into rate equation models of the nonlinear light-matter interaction.

The aim is a detailed, material-specific description of the ionization processes during the interaction of ultrashort laser pulses with the dielectric material. The subproject is focused on investigation of transparent amorphous materials without any periodicity in the long-range order. These will be validated before the background of well-studied monocrystalline modifications of these materials.

In addition, the combination of different simulation techniques in a virtual coater concept will allow to study the material properties from an atomistic point of view. The developed approach in subproject TP6 provides a complete description of the optical properties for complex amorphous materials as a function of thin film nucleation on the basis of experimental coating parameters. Simultaneously, the chosen model approach offers the possibility to determine material properties, which are hardly accessible experimentally or by comparable theoretical approaches.