Together with Jan Wiersig from Magdeburg/Germany, we just published an article in Reports on Progress in Physics (open access) that combines two research thrusts in our group: Fisher information (FI) and Exceptional Points (EPs). We demonstrate how EPs can enhance the FI and how moving away from the EP can lead to an even greater improvement in measurement precision. Our work establishes a general framework for understanding the role of non-Hermitian degeneracies in parameter estimation and clarifies under which conditions EPs provide genuine metrological advantages.

A joint paper with colleagues from Graz and Cardiff has just appeared in Laser & Photonics Reviews. In this work, we develop a resonant-state theory for finite photonic systems that are periodically modulated in time. While these photonic time crystals are often discussed in terms of bulk bandgaps, realistic implementations are finite and open. We show that their dynamics is governed by resonant states (quasinormal modes), revealing how parametric amplification emerges as a resonant process. Congratulations to Adrià, Sergei, David, Egor, Thomas and everyone involved!