The AB transition in Superfluid 3He

TL;DR

This paper reviews the history and significance of the AB transition in superfluid helium-3, highlighting its role in understanding fermionic superfluidity and related quantum phenomena.

Contribution

It provides a focused retrospective on the AB transition in superfluid 3He, emphasizing its importance in the development of quantum fluid research.

Findings

Historical discovery of superfluid phases in 3He

Significance of the AB transition in quantum fluid studies

Impact on subsequent research in fermionic superfluids

Abstract

The discovery of superfluidity in 3He in 1971, published in 1972, [1, 2] has influenced a wide range of investigations that extend well beyond fermionic superfluids, including electronic quantum ma- terials, ultra-cold gases and degenerate neutron matter. Observation of thermodynamic transitions from the 3He Fermi liquid to two other liquid phases, A and B-phases, along the melting curve of liquid and solid 3He, discovered by Osheroff, Richardson, and Lee, were the very first indications of 3He superfluidity leading to their Nobel prize in 1996. This is a brief retrospective specifically focused on the AB transition.