jobs!

How to apply

Please contact Lars Pastewka about these positions (and possibly other openings not posted here). We are a simulation group and do not conduct any experiments in the group. We are looking for candidates with the following profile:

  • Modeling: You feel comfortable working with physical models, i.e. you understand how to describe the physical world around you in terms of differential equations.
  • Coding: You have experience in writing codes that carry out numerical calculations or analyze data. Ideally, you have used Python, C++ or Rust.
  • Simulation: You have written simulation codes or codes to evaluate simulation output yourself.

Please do not apply if your only experience with simulations is running a simulation package, with the exception of molecular dynamics packages (e.g. LAMMPS or GROMACS).

For applying, please send:

  • Letter of motivation: Why do you apply for this position? Keep it short.
  • Curriculum vitae: What is your experience?
  • Academic track record: Grades from all BSc and MSc programs that you attended
  • References: List of advisors that would be able to provide recommendation letters (PhD or Postdoc only)

PhD or Postdoc projects

Hydrogels

We are looking for a PhD student or postdoc to work on the mechanics of hydrogels using coarse-grained molecular dynamics techniques. The project involves developing strategies to build representative hydrogel models as we all developing methods to characterize the mechanical response of these fluctuation, dominated materials. This includes bulk elastic moduli, fracture and friction.

Relevant publications and further reading: Mees et al., Tribol. Lett. (2023), Mees, O’Connor, Pastewka, J. Chem. Phys. (2023)

Lubrication

We are looking for two PhD candidates on developing multiscale simulation methods for lubrication. The microscopic processes underlying friction and lubrication have so far eluded quantitative description. The PhD project aims at developing cross-scale simulation methods for the modeling of such processes. Here, the local viscoelastic material properties within the lubrication gap are to be described with molecular dynamics simulation methods and coupled to a global fluid mechanics simulation. Furthermore, the obtained pressure distribution in the lubrication gap leads to the deformation of the contacting solids, which is to be described by means of boundary element methods. The work is embedded into the DFG research training group “Tailored Scale-Bridging Approaches to Computational Nanoscience” (GRK 2450) and builds on results results obtained from a prior cohort of PhD students, who developed a continuum mechanical solver which is in principle suitable for such a coupling.

Relevant publications and further reading: Holey, Codrignani, Gumbsch, Pastewka, Tribol. Lett. (2022)

Soft adhesion

We are looking looking for a PhD candidate or postdoc on the theoretical study of adhesion of soft materials in contact with rough interfaces. You will employ continuum simulation techniques (boundary element method and line tension models) as well well as mathematical analytic tools. This includes the incorporation of material disorder into numerical solutions of continuum mechanical problems. We expect a strong background in continuum mechanics and some experience with software development, ideally in Python. The project is embedded within the DFG priority program on “Variational Methods for Predicting Complex Phenomena in Engineering Structures and Materials” (SPP 2256). An companion position will be filled in Applied Mathematics at the University of Freiburg in the group of Patrick Dondl.

Relevant publications and further reading: Sanner, Pastewka, JMPS (2022), Sanner et al., arXiv (2023)

MSc or BSc projects

Molecular simulation of wall slip

Supervision: Hannes Holey, Lars Pastewka

When fluids are confined to only a few nanometers, the no-slip condition usually employed at fluid wall interfaces breaks down. Molecular dynamics (MD) simulations have been used to quantify slip both in equilibrium and under shearing conditions. Accurate descriptions of the highly nonlinear slip behavior is crucial, for instance to describe lubricated friction under extreme conditions. The goal of this thesis is to test a recently proposed method that measures slip in equilibrium MD simulations . Compared to previous studies, the viscosity of the confined fluid is not required as an input parameter but can be inferred from the spectral attenuation behavior of collective fluctuations. Starting with simple interatomic potentials and planar slit geometries, the method shall be extended to cylincdrical nanopores such as carbon nanotubes filled with water.

Relevant publications and further reading: Sam et al., Nanotechnology (2018), Holey, Gumbsch, Pastewka, arXiv (2023)