Traditionally, observing ultracold atoms is a destructive process that requires preparing a new atomic cloud for each measurement. During his PhD, Laurits Stokholm developed a novel non-destructive technique based on single-photon detection and dark-ground imaging, enabling real-time observation of quantum systems with minimal disturbance. This approach reduces data acquisition times from hours to minutes.

In addition, he investigated room-temperature Rydberg atoms for a new type of microwave polarimeter.
The new research findings contribute to the quantum engineering toolbox for high-precision AMO experiments.

The PhD study was completed at the Department of Physics and Astronomy (IFA), Faculty of Natural Sciences, Aarhus University.

This summary was prepared by the PhD student.

Time: Wednesday, 6^th of May 2026 at 14:30
Place: Physics Auditorium, 1523-318, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus
Title of PhD thesis: Real-Time Quantum Sensing in Rubidium: Few-Photon Probing of Ultracold Gases and Rydberg Microwave Polarimetry
Contact information: Laurits Stokholm, e-mail: lstokholm@phys.au.dk, tel.: +45 53357755
Members of the assessment committee:
Professor Dr. Klaus Sengstock, Institute for Quantum Physics, University of Hamburg, Germany
Senior Scientist Dr. Robert Löw, Physikalisches Institut, University of Stuttgart, Germany
Chair: Associate Professor Brian Julsgaard, Department of Physics and Astronomy, Aarhus University, Denmark
Main supervisor: Professor Dr. Jan Joachim Arlt, Department of Physics and Astronomy, Aarhus University, Denmark
Language: The PhD dissertation will be defended in English

The defence is public.
The PhD thesis is available for reading at the Graduate School of Natural Sciences/GSNS, Ny Munkegade 120, building 1521, 8000 Aarhus C