The angular momentum of a magnetically trapped atomic condensate

TL;DR

This paper explores how angular momentum components in magnetically trapped atomic condensates relate to gauge potentials, revealing new insights into their vorticity and conservation laws in different magnetic trap configurations.

Contribution

It uncovers the conservation properties of angular momentum components in various magnetic traps and links these to gauge potentials induced by the adiabatic approximation.

Findings

Sum of axial angular momentum and hyperfine spin is conserved in symmetric traps.

Difference of these components becomes conserved in non-axially symmetric Ioffe-Pritchard traps.

Provides new understanding of vorticity in magnetically trapped quantum gases.

Abstract

For an atomic condensate in an axially symmetric magnetic trap, the sum of the axial components of the orbital angular momentum and the hyperfine spin is conserved. Inside an Ioffe-Pritchard trap (IPT) whose magnetic field (B-field) is not axially symmetric, the difference of the two becomes surprisingly conserved. In this paper we investigate the relationship between the values of the sum/difference angular momentums for an atomic condensate inside a magnetic trap and the associated gauge potential induced by the adiabatic approximation. Our result provides significant new insight into the vorticity of magnetically trapped atomic quantum gases.