Spin Waves in Quantum Gases --- The Quality Factor of the Identical Spin Rotation Effect

TL;DR

This paper revisits the theory of the Identical Spin Rotation Effect (ISRE) in dilute gases, deriving asymptotic formulas for its quality factor based on recent experimental insights into electron spin waves in atomic hydrogen.

Contribution

It provides new asymptotic formulas for the ISRE quality factor and evaluates their accuracy for hydrogen and helium-3 gases.

Findings

Derived asymptotic formulas for the ISRE quality factor.

Validated formulas against experimental data for hydrogen and helium-3.

Enhanced understanding of spin wave properties in dilute gases.

Abstract

Our recent experimental work on electron spin waves in atomic hydrogen gas has prompted a revisit of the theory of the Identical Spin Rotation Effect (ISRE). A key characteristic determining the properties of the spin waves is the quality factor of ISRE. Unfortunately, calculating this quality factor takes some toil. In this paper we summarize some results of the ISRE theory in dilute gases. We also derive asymptotic formulae for the quality factor and examine their accuracy for hydrogen and $^3$He.