Scissors mode of dipolar quantum droplets of dysprosium atoms

TL;DR

This paper reports the observation of the scissors mode in a dipolar quantum droplet of dysprosium atoms, revealing insights into internal interactions and providing a new spectroscopic method for studying such systems.

Contribution

It introduces a novel spectroscopic technique based on magnetic field orientation modulation to study dipolar quantum droplets and extracts the background scattering length for dysprosium.

Findings

Observation of the scissors mode in a single dipolar quantum droplet

Development of a magnetic field modulation technique for spectroscopy

Establishment of an analogy between quantum droplets and atomic nuclei

Abstract

We report on the observation of the scissors mode of a single dipolar quantum droplet. The existence of this mode is due to the breaking of the rotational symmetry by the dipole-dipole interaction, which is fixed along an external homogeneous magnetic field. By modulating the orientation of this magnetic field, we introduce a new spectroscopic technique for studying dipolar quantum droplets. This provides a precise probe for interactions in the system allowing to extract a background scattering length for \textsuperscript{164}Dy of $69(4)\,a_0$. Our results establish an analogy between quantum droplets and atomic nuclei, where the existence of the scissors mode is also only due to internal interactions. They further open the possibility to explore physics beyond the available theoretical models for strongly-dipolar quantum gases.