Three intersecting circles containing the names of three research areas: ‘Out-of-equilibrium phenomena’, ‘Many-body quantum optics’ and ‘Strongly correlated phases of matter’. A red dot marks the point of intersection and a line indicates: 'You are here’.

© M. Ciardi

Our research group is dedicated to the theoretical investigation of complex quantum systems, where strong particle interactions and coupling to light give rise to novel collective phenomena. At the heart of our work lies the fundamental question of how quantum phases and emergent properties arise from microscopic interactions. A particular focus is placed on open many-body systems, where the interplay between dissipation and controlled external driving can lead to the formation of unconventional quantum phases and non-classical states.

These questions are closely linked to the control of light–matter interactions in modern experimental platforms, such as ultracold atomic gases or Rydberg atoms in optical lattices and resonators, as well as in solid-state systems.

To describe these systems, we employ a combination of analytical and numerical methods, including cumulant expansions, density matrix techniques, and quantum Monte Carlo simulations. Our goal is to identify, understand, and harness new quantum effects – both in the context of fundamental questions in quantum physics and with a view towards future applications in quantum optics and quantum information.

Current Research Topics

Non-equilibrium physics of open quantum systems and time crystals

We explore how quantum coherence can be preserved or deliberately generated under dissipative conditions. Our focus lies in dynamic ordering phenomena such as quantum time crystals in nonlinear media.

Collective radiation effects and superradiance

In strongly correlated atomic systems or solid-state structures, light can be emitted cooperatively. We investigate how these collective effects can be harnessed to generate and control quantum states of light.

Interacting photons in ordered structures

Under specific conditions, photons can acquire effective interactions via coupling to matter systems. We study how such synthetic photon–photon interactions can arise in optical lattices or resonators and how they may be exploited for quantum technologies.

Dipolar quantum matter

Long-range dipolar interactions offer exciting opportunities to realise novel many-body systems with strong correlations. Our research explores how such interactions in ultracold atoms and molecules can be controlled to create exotic quantum phases, such as quantum fluids or supersolid structures.