IQIM Postdoctoral and Graduate Student Seminar

Abstract: Entanglement is at the heart of quantum many-body physics, and is theoretically used to characterize quantum phase transitions and topological order. Detecting entanglement in experimental systems, however, is hard as it often requires a full reconstruction of the density matrix or prior knowledge about the state itself. Instead, in our experiments with interacting bosonic ultra cold atoms we rely on the general property of a bipartite entangled state that ignoring information about (or tracing over) one subsystem introduces a classical mixture in the other. This results in an increased Renyi entanglement entropy that we directly measure by interfering two identically prepared copies of a few-body state.