Superfluids in rotation: Landau-Lifshitz vortex sheets vs Onsager-Feynman vortices

TL;DR

This paper reviews the historical development and experimental confirmation of Landau-Lifshitz vortex sheets in rotating superfluids, especially in superfluid 3He-A, highlighting their significance alongside Feynman's vortices.

Contribution

It clarifies the experimental validation of Landau-Lifshitz vortex sheet theory in superfluid 3He-A and discusses various observed configurations.

Findings

Vortex sheets confirmed in superfluid 3He-A

Landau-Lifshitz equation validated experimentally

Different vortex sheet configurations observed

Abstract

The paper by Landau and Lifshitz on vortex sheets in rotating superfluid appeared in 1955 almost at the same time when Feynman published his paper on quantized vortices in superfluid 4He. For a long time this paper has been considered as an error. But 40 years later the vortex sheets have been detected in chiral superfluid 3He-A in the rotating cryostat constructed in the Olli Lounasmaa Low Temperature Laboratory (Otaniemi, Finland). The equation derived by Landau and Lifshits for the distance between the vortex sheets as a function of the angular velocity of rotation has been experimentally confirmed, which is the triumph of the theory. We discuss different configurations of the vortex sheets observed and to be observed in superfluid 3He-A.