Vortex-antivortex wavefunction of a degenerate quantum gas

TL;DR

This paper explores the formation and properties of vortex-antivortex wavefunctions in a degenerate quantum gas, revealing how optical vortex arrays influence matter wave angular momentum and create complex labyrinth-like phase structures.

Contribution

It introduces a separable Hamiltonian model for vortex-antivortex states in pancake traps and demonstrates the formation of antiferromagnet-like matter waves with unique angular momentum properties.

Findings

Optical vortex arrays can pin and organize matter wave vortices.

The 3D wavefunction is factorized into harmonic oscillator and vortex-antivortex components.

The resulting quantum state has zero angular momentum but nonzero rotational energy.

Abstract

A mechanism of a pinning of the quantized matter wave vortices by optical vortices in a specially arranged optical dipole traps is discussed. The vortex-antivortex optical arrays of rectangular symmetry are shown to transfer angular orbital momentum and form the "antiferromagnet"-like matter waves. The separable Hamiltonian for matter waves in pancake trapping geometry is proposed and 3D-wavefunction is factorized in a product of wavefunctions of the 1D harmonic oscillator and 2D vortex-antivortex quantum state. The 2D wavefunction's phase gradient field associated via Madelung transform with the field of classical velocities forms labyrinth-like structure. The macroscopic quantum state composed of periodically spaced counter-rotating BEC superfluid vortices has zero angular momentum and nonzero rotational energy.