Thomas Krieguer is a PhD student in quantum physics with a Master’s degree in Quantum Light-Matter and Nanotechnologies from Paris-Saclay University. With expertise in open quantum systems, non-linear physics, and light-matter interaction, Thomas’s research is centered on developing a fully fermionic theoretical model to explore ultra-strong coupling between cavity-mode light and electronic subbands. This advanced model goes beyond the rotating wave approximation to study complex phenomena such as polaritons, the dynamical Casimir effect, and the Bloch-Siegert shift, contributing significantly to the understanding of non-linear generation in cavity-coupled electronic subbands. Thomas’s work not only enhances theoretical insights but also aids in predicting and optimizing the responsivity of quantum cascade photodetectors. His model is frequently applied to highly doped semiconductor heterostructures embedded in patch cavities, particularly in quantum cascade detectors, to deepen understanding of electronic transport mechanisms and support the development of enhanced device designs.