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Our group conducts experiments on the following topics: thermodynamics of light, as Bose-Einstein condensation of photons in microcavities, and the statistics and dynamics of photons in tailored potentials. We also investigate topology and quantum simulation with ultracold atomic gases.

We are always looking for Bachelor, Master, PhD students, and postdocs. For more information, see here.

Latest news

Quantum Gases of Light Exhibit Critical Behavior

In collaboration with Heidelberg University and the National Autonomous University of Mexico (UNAM), we investigated the critical behavior of photons near a phase transition. In doing so, we succeeded for the first time in demonstrating critical scaling behavior in a quantum gas of light. The results of first author Leon Kleebank were published in Science Advances.

Dr. Kevin Peters awarded Walter Benjamin Scholarship from the DFG

During the Walter Benjamin project, Dr. Peters will conduct research on photon Bose–Einstein condensation and non-equilibrium quantum optics. The project focuses on the condensation of photons directly into quantum-entangled states, using optical cavity experiments combined with laser spectroscopy, real-time detection, and theoretical modelling. The work aims to advance the understanding of driven-dissipative many-body quantum systems and to establish new approaches for generating and controlling quantum states of light.

Statistics at the limit: Our paper on thermodynamics in two-state systems is published

Thermodynamics is usually associated with large systems in which many particles can be distributed across a large number of states. But even systems in which few particles can be distributed across only two states follow thermodynamic laws, as the work of Christian and Andreas shows. This may enable the construction of novel light sources in the future that combine the advantages of lasers with those of incandescent lamps.

Periodic driving of a condensate reveals elementary excitations of photons coupled to a bath

A photon Bose–Einstein condensate (BEC) is a state of light in which photons occupy the ground state of an optical cavity when equilibrating with a material in thermal equilibrium — for example, molecules at room temperature. Due to the incoherent coupling between photons and molecules, the system exhibits new resonances, which can be linked to elementary excitations of the coupled system, which allow to gain deeper insight into the intricate link between coupling, drive and dissipation.