T3: Superfluidity in Strong Dipolar Quantum Gases

• Applicant: Privatdozent Dr. Axel Pelster
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 258183570

Within the second period of the Research Unit, this new theory project will analyze the emergence of superfluidity in strong dipolar quantum gases.One focus will be on studying dipolar fermions in a harmonic trap, where the Fermi sphere has already been shown to be deformed into an ellipsoid following the orientation of the dipoles. At first, we will investigate to which degree also the spatial distribution of the fermions follows the dipolar preference direction. Afterwards we will consider for such a general geometry dynamical aspects, like a non-ballistic expansion or collective excitations. Based on these results we will then come to the major question how the superfluid pairing in a single-component dipolar Fermi gas, which has been predicted some time ago, is modified by the deformation of the Fermi sphere. In addition, we will also join the quest of the Research Unit for a better understanding of the anisotropic superfluid properties of quantum droplets, which arise in a strong dipolar Bose gas. To this end we will investigate how quantum mechanical and thermal fluctuations affect the stability of dipolar quantum droplets and their anisotropic velocity of sound. Furthermore, we will be interested in the onset of quantum droplets in fast-rotating dipolar Bose-Einstein condensates and consider whether the presence of vortices enhances this process.

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