A two-dimensional ultracold gas of fermionic polar LiCs molecules

• Applicant: Professor Dr. Matthias Weidemüller
• 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

The aim of this project is to produce a dipolar quantum gas of fermionic LiCs molecules to study few- and many-body effects under the influence of long-range dipolar interaction. LiCs features a dipole moment of 5.5 Debye in the rovibrational ground state. Such a large dipole moment is ideally suited to explore the effects of strong dipolar interactions, as occurring for example in dipolar crystals, spin models, and super solid phases. In order to investigate these phenomena, the gas of fermionic polar molecules will be stabilized against inelastic collisional loss by optically confining it in a 2D geometry allowing for the control over the few-body chemical reactions and for the development of a comprehensive understanding of the underlying few-body collisional processes. The creation of the ultracold molecules is based on the production of weakly bound Feshbach molecules in a double-degenerate mixed atomic gas of 6Li and 133Cs in an optical dipole trap and subsequent STIRAP to the rovibrational ground state. The dipolar interaction will be controlled by microwave electric fields. In the course of this research program we will develop strategies for an increase of the phase space density by evaporative cooling of polar molecules. The combination of a stabilized gas of polar molecules and strong dipolar interaction energy makes it possible to explore the dipolar quantum gas under equilibrium and out-of-equilibrium conditions.

• DFG Programme: Research Units
• Subproject of: FOR 2247: From few to many-body physics with dipolar quantum gases