Stable Spin Precession at one Half of Equilibrium Magnetization in Superfluid 3He-B

TL;DR

This paper reports the discovery of new stable spin precession modes in superfluid 3He-B, including a mode with half the equilibrium magnetization, expanding understanding of spin superfluid states near the transition temperature.

Contribution

It introduces and characterizes new stable dynamical order parameter states with fractional magnetization in superfluid 3He-B, including the second phase correlated spin superfluid state.

Findings

Identified stable precession modes with magnetization p=1, 1/2, and ~0.

Observed stability of these states in CW NMR near T_c.

Demonstrated excitation of these states within a narrow temperature range.

Abstract

New stable modes of spin precession have been observed in superfluid 3He-B. These dynamical order parameter states include precession with a magnetization S=pS_{eq} which is different from the equilibrium value S_{eq}. We have identified modes with p=1, 1/2 and \approx 0. The p=1/2 mode is the second member of phase correlated states of a spin superfluid. The new states can be excited in the temperature range 1-T/T_c \lesssim 0.02 where the energy barriers between the different local minima of the spin-orbit energy are small. They are stable in CW NMR due to low dissipation close to T_c.