Evidence of superfluidity in a dipolar supersolid from non-classical rotational inertia

Year: 2021

Authors: Tanzi L., Maloberti J.G.,
Biagioni G., Fioretti A., Gabbanini C., Modugno G.

Autors Affiliation: CNR-INO, Sede Secondaria di Pisa, 56124 Pisa, Italy.
LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy

Abstract: A key manifestation of superfluidity in liquids and gases is a reduction of the moment of inertia under slow rotations. Non-classical rotational effects have been searched for a long time also for the elusive supersolid phase of matter, in which superfluidity coexists with a lattice structure. Here we show that the recently discovered supersolid phase in dipolar quantum gases features a reduced moment of inertia. We study a peculiar rotational oscillation mode in a harmonic potential, the scissors mode, already employed for superfluids. From the measured moment of inertia, we infer a superfluid fraction that is different from zero and of order of unity, providing direct evidence of the superfluid nature of the dipolar supersolid.


Volume: 371      Pages from: 1162  to: 1165

KeyWords: quantum gases, supersolid
DOI: DOI: 10.1126/science.aba4309