A Bose-Einstein condensate coupled to an optical cavity shows the Dicke quantum phase transition in an open system. The superradiant phase emerges from a broken symmetry and has the character of a supersolid. I will report on experiments characterizing the supersolid phase and investigating the soft mode when approaching the phase transition. I will further report on a novel scheme to highly locally probe spin fluctuations in a two-component Fermi gas.
Tilman Esslinger is full professor at the Physics Department of ETH Zurich and received his PhD from the Ludwig-Maximilians-University in Munich. In his research he uses ultracold atoms to synthetically create and study key models of quantum many-body physics. He pioneered bosonic and fermionic Hubbard models, one dimensional quantum gases and atom lasers. Most recently, he and his team have been able to observe the Dicke quantum phase transition in a superfluid coupled to an optical cavity.