Superfluid $\beta$ phase in liquid $^3$He

TL;DR

This paper reports the first experimental observation of the superfluid $eta$ phase in liquid helium-3 within nematic aerogel under high magnetic fields, expanding understanding of superfluid phases.

Contribution

It introduces the first detection and characterization of the superfluid $eta$ phase in $^3$He using a vibrating aerogel resonator.

Findings

First observation of superfluid $eta$ phase in $^3$He

Identification of the phase in nematic aerogel under high magnetic field

Measurement of the phase's existence region

Abstract

We report the first observation of superfluid $\beta$ phase of $^3$He. This phase is realized in $^3$He in nematic aerogel in presence of high magnetic field right below the superfluid transition temperature. We use a vibrating aerogel resonator to detect the transition to the $\beta$ phase and measure the region of existence of this phase.