Quantum Metrology and Fundamental Physics - University Tübingen, Germany

Session

Wednesday Morning 2

15 Jul 2026, 11:00

12. Searching for Solar Dark Photons and Axions with Coherent Two-Photon Transitions

Rohan Kulkarni (Queen's University)

15/07/2026, 11:00

Session 2

Abstract. Two-photon transitions in a coherently prepared atomic medium support cooperative emission rates that scale as $N^{2}$, where $N$ is the number of emitters in the coherence volume. Because the two signal photons are emitted back-to-back, their momenta cancel and the Dicke phase-matching constraint met, so that the coherence volume can be made macroscopic. Together these features make...

3. Searching for Sub-GeV Dark Matter with superfluid helium

Felix Kahlhoefer (Karlsruhe Institute of Technology)

15/07/2026, 11:45

Session 2

I will present novel ideas to search for the scattering of dark matter particles with mass below the GeV scale using superfluid helium detectors. First, I will introduce the upcoming DELight experiment, which will use magnetic microcalorimeters to detect photons and collective excitations produced by dark matter scattering. The sensitivity of such a search can be extended further by...