Rotating a supersolid dipolar gas

TL;DR

This paper investigates the rotational properties of a dipolar Bose-Einstein condensate as it transitions from superfluid to supersolid, revealing key features like jumps in moment of inertia and vortex core deformation.

Contribution

It provides a detailed analysis of the moment of inertia and vortex structures across the superfluid to supersolid transition in dipolar gases.

Findings

Jump in moment of inertia at superfluid-supersolid transition

Frequency of scissors mode affected by superfluidity reduction

Deformed vortex cores in the supersolid phase

Abstract

Distintictive features of supersolids show up in their rotational properties. We calculate the moment of inertia of a harmonically trapped dipolar Bose-Einstein condensed gas as a function of the tunable scattering length parameter, providing the transition from the (fully) superfluid to the supersolid phase and eventually to an incoherent crystal of self-bound droplets. The transition from the superfluid to the supersolid phase is characterized by a jump in the moment on inertia, revealing its first order nature. In the case of elongated trapping in the plane of rotation we show that the the moment of inertia determines the value of the frequency of the scissors mode, which is significantly affected by the reduction of superfluidity in the supersolid phase. The case of isotropic trapping is instead well suited to study the formation of quantized vortices, which are shown to be characterized, in the supersolid phase, by a sizeable deformed core, caused by the presence of the sorrounding density peaks.