Quantum dynamics of strongly correlated RbCs dipolar quantum gases

• Applicant: Professor Dr. Hanns-Christoph Nägerl
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 258183570

Ultracold atoms and molecules confined to lattice potentials offer myriad possibilities for the controlled preparation and study of strongly correlated quantum many-body systems. For atoms, milestones in the field have been the experimental realization of the Hubbard model of condensed matter physics and the observation of the superfluid-to-Mott-insulator phase transition for systems with local contact interactions. Molecules have the potential to greatly broaden the spectrum of strongly correlated quantum systems that can be investigated. In particular, dipolar molecules with their long-range and orientation dependent electric dipole-dipole interaction provide new opportunities to probe e.g. novel forms of superfluidity and interesting many-body ground states (such as dipolar crystals, supersolids, fractional Mott insulators, quantum magnets,…) in conjunction with novel quantum phase transitions, and in general non-equilibrium quantum many-body dynamics.This project is aimed at studying the dynamics of ultracold RbCs dipolar bosons confined to one- and two-dimensional geometry and lattice potentials. The RbCs dipoles, initially prepared from atom pairs located at individual sites of an optical lattice at high filling fraction, will be studied in the regimes of frozen spins (i.e. fixed spatial location in the lattice) and in the regime of mobile dipoles. We will explore to what extent one can realize novel many-body spin models, with possible applications to the field of quantum simulation, and study the stability, dynamics and relaxation processes for many-body systems composed of quantum dipoles confined to low-dimensional geometry. In particular, our project aims at testing in experiments the dynamical processes as allowed by the extended Hubbard model, i.e. the Hubbard model augmented by terms modeling off-site interaction terms. The project is based on an existing Rb-Cs quantum gas mixture apparatus (set up over several years within the Austrian SFB FoQuS, funded by the FWF) for which we have implemented efficient ground-state transfer of ultracold RbCs molecules into a specific hyperfine sublevel of the RbCs ground-state molecule and for which we have demonstrated high molecular filling fraction in a three-dimensional lattice potential.

• DFG Programme: Research Units
• Subproject of: FOR 2247: From few to many-body physics with dipolar quantum gases
• International Connection: Austria
• Partner Organisation: Fonds zur Förderung der wissenschaftlichen Forschung (FWF)