Einstein-de Haas Effect in a Dipolar Fermi Gas

TL;DR

This paper predicts an Einstein-de Haas-like effect in ultracold dipolar Fermi gases, where dipole interactions cause magnetization to transfer into orbital motion, with unique twisting dynamics that could be experimentally observed.

Contribution

It introduces a novel Einstein-de Haas effect analogue in dipolar Fermi gases, highlighting the role of Fermi surface deformation and controllable twisting motion.

Findings

Magnetization transfers to orbital angular momentum due to dipole interactions.

Distinct twisting motion with opposite rotations of spin components.

Potential method for measuring scattering lengths of dipolar atoms.

Abstract

We show that an analogue to the classical Einstein-de Haas effect can appear in ultracold dipolar Fermi gases. The anisotropic nature of dipole-dipole interactions can lead to a transfer of magnetization into orbital angular momentum. Remarkably, distinct from a Bose-Einstein condensate, this transfer is accompanied by twisting motion, where individual spin components rotate in opposite directions with larger orbital angular momenta than the full system, possibly leading to easier experimental observation of the effect. This feature is induced by the deformation of the Fermi surface and the direction of the twisting motion can be controlled by an s-wave scattering length or external magnetic field, possibly providing a method of measuring scattering lengths of strongly dipolar atomic species.