Gesloten vacatures Est

The Department of Earth Sciences is looking for a highly motivated PhD candidate with a MSc background in Earth Sciences or another appropriate field. You will work on the project Nanoscale Rock Magnetism and Magnetic Imaging.

This study is part of the ERC Consolidator project SPARK, which aims to unlock magnetic information stored in nanoscale vortex‑state particles in rocks and other geological materials. These tiny particles may preserve key information on the strength and behaviour of the geomagnetic field during critical periods in Earth’s history, such as the early Earth, the great oxygenation event, and step‑changes in the evolution in the Devonian and Ediacaran. Despite their potential, the recording behaviour and long‑term magnetic stability of these vortex‑state particles are still poorly understood. In this project, you will experimentally investigate which vortex‑state particles are reliable recorders of the Earth’s magnetic field and how to obtain the crucial information hidden within them.

Your research will focus on the empirical characterization of individual magnetic particles, combining state‑of‑the‑art magnetic imaging with advanced electron microscopy techniques. You will generate high‑quality experimental datasets that form the basis for data‑driven micromagnetic modelling developed within the project.

• Acquiring nanoscale magnetic measurements using Quantum Scanning Microscopy and wide‑field Quantum Diamond Microscopy.
• Characterizing particle geometry in three dimensions using slice‑and‑view FIB‑SEM analysis.
• Determining mineralogical and chemical properties (composition, zoning, crystallographic orientation) using complementary electron microscopy techniques.
• Working closely with a postdoctoral researcher to use your experimental observations as constraints for micromagnetic simulations, systematically assessing how size, shape, and mineralogy control magnetic stability.
• Presenting your findings at international conferences and publishing in peer‑reviewed journals.

You will be supervised by Dr Lennart de Groot and work closely with a postdoctoral researcher, who focuses on the data‑driven development of micromagnetic modelling tools, as well as with a PhD candidate focusing on the paleomagnetic information stored in (statistical) ensembles of vortex‑state particles. Together, you will integrate experimental observations and computational modelling to establish a robust framework for identifying which vortex‑state particles reliably record the Earth’s magnetic field.

The project is embedded in the Paleomagnetic Laboratory Fort Hoofddijk, which hosts two Quantum Diamond Microscopes and a Quantum Scanning Microscope, enabling magnetic imaging at spatial resolutions from micrometres down to the nanometre scale. Advanced FIB‑SEM facilities are available at Utrecht University’s Electron Microscopy Center. The project further benefits from excellent dedicated CPU and GPU computing infrastructure to support large‑scale numerical modelling and data analysis. You will receive extensive training in these techniques as part of your PhD project and will work in an international, multidisciplinary research environment.

At the start of your PhD, a personalised training programme will be established reflecting your training needs and career objectives. About 20% of your time will be dedicated to this training component, which includes following courses/workshops as well as training on the job in assisting in the Bachelor’s and Master’s programmes of the department at Utrecht University.