Anisotropic relaxation dynamics in a dipolar Fermi gas driven out of equilibrium

Abstract

We report on the observation of a large anisotropy in the rethermalization dynamics of an ultracold dipolar Fermi gas driven out of equilibrium. Our system consists of an ultracold sample of strongly magnetic ${}^{167}$Er fermions, spin-polarized in the lowest Zeeman sublevel. In this system, elastic collisions arise purely from universal dipolar scattering. Based on cross-dimensional rethermalization experiments, we observe a strong anisotropy of the scattering, which manifests itself in a large angular dependence of the thermal relaxation dynamics. Our result is in very good agreement with recent theoretical predictions. Furthermore, we measure the rethermalization rate as a function of temperature for different angles and find that the suppression of collisions by Pauli blocking is not influenced by the dipole orientation.

5 pages, 4 figures

References in corpus (6)

• Theory of ultracold Fermi gases
• Bose-Einstein Condensation of Erbium
• d-wave collapse and explosion of a dipolar Bose-Einstein condensate
• Production of quantum degenerate strontium gases: Larger, better, faster, colder
• Observation of Fermi surface deformation in a dipolar quantum gas
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Cited by in corpus (12)

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• Cooling and thermometry of atomic Fermi gases
• Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Liquid quantum droplets of ultracold magnetic atoms
• Collisionally Stable Gas of Bosonic Dipolar Ground State Molecules
• Accurate determination of the scattering length of erbium atoms
• Anisotropic thermalization of dilute dipolar gases
• Nonequilibrium dynamics of an ultracold dipolar gas
• Anisotropic collisions of dipolar Bose-Einstein condensates in the universal regime
• Linear Response of a Periodically Driven Thermal Dipolar Gas
• Multiple polaron quasiparticles with dipolar fermions in a bilayer geometry
• Strongly dipolar molecular Bose-Einstein condensates: From few- to many-body physics