Academic Research

In our experiments, we generate nano-sized particles from simple molecules like water, carbon dioxide, and hydrocarbons in the gas phase, with particle size ranging from a few to a few million molecules per particle. This is achieved using a pulsed supersonic jet generated by the adiabatic expansion of pure gas under high pressure into vacuum. We control the mean particle size via source pressure and temperature and determine it optically by time- and space-resolved laser-induced Rayleigh scattering. Our experimental setup allows for very precise control of the experimental parameters and also for a very wide range of pressure and temperature, enabling the investigation of jet expansions from liquids and supercritical fluids as well. In these regimes, particles form through a different mechanism, namely the breakup of liquids and supercritical fluids.

Why are these phenomena fascinating, why does the scientific community care about it, and why does it make it an exceptional internship topic:

1) How do a few molecules suddenly decide to stick together and grow into a particle? Understanding this initial step of nucleation is incredibly complex because these clusters of molecules are unstable and temporary. Phase transitions of gas molecules to liquid or solid nanoparticles bridge the gap between quantum mechanics and bulk, classical physics. The process of elastic light scattering allows detection of tiny nanoparticles non-invasively in real time: By shining a laser through the jet, the intensity of the scattered light tells instantly when particles are forming and how big they are.

2) Researching this topic has direct implications for the environment (climate change, atmospheric science, pollution control), industry (gas phase synthesis of pristine, high-purity nanoparticles used in electronics, catalysts, and advanced materials), and astrochemistry (interstellar dust clouds and the atmospheres of other planets ).

3) An internship in this field offers a perfect blend of fundamental science and technical skills: you will gain deep knowledge in optics and lasers, thermodynamics, and chemistry, get hands-on experience with advanced experimental setups, including working with vacuum systems and precision optical diagnostics (lasers and detectors). and develop strong data analysis and possibly even coding skills. You will be working on a topic that directly addresses modern global challenges, making your resume stand out for both future academic positions and R&D jobs in industry.

The main tasks will be to start the experiment by setting the various instrument parameters, run the (largely computer controlled) experiment, acquire data during the day and mostly focus on data evaluation and analysis.

You will receive more information from your supervisor about two months before the start of the project