Coreless vortex ground state of the rotating spinor condensate

TL;DR

This paper investigates the ground states of rotating spinor condensates, revealing the formation of coreless vortices in ferromagnetic cases and unique angular momentum behavior in anti-ferromagnetic cases, with implications for quantum fluid dynamics.

Contribution

It demonstrates the existence of a critical rotation frequency for coreless vortex formation and compares behaviors between ferromagnetic and anti-ferromagnetic spinor condensates.

Findings

Coreless vortices form at slow rotation in ferromagnetic condensates.

Critical rotation frequency for vortex creation decreases with system size.

Anti-ferromagnetic condensates show a half-integer angular momentum step.

Abstract

We study the ground state of the rotating spinor condensate and show that for slow rotation the ground state of the ferromagnetic spinor condensate is a coreless vortex. While coreless vortex is not topologically stable, we show that there is an energetic threshold for the creation of a coreless vortex. This threshold corresponds to a critical rotation frequency that vanishes as the system size increases. Also, we demonstrate the dramatically different behavior of the spinor condensate with anti-ferromagnetic interactions. For anti-ferromagnetic spinor condensate the angular momentum as a function of rotation frequency exhibits the familiar staircase behavior, but in contrast to an ordinary condensate the first step is to the state with angular momentum 1/2 per particle.