Vortices and Edge Reconstruction in Small Quantal Systems at High Angular Momenta

TL;DR

This paper investigates vortex formation and edge reconstruction in small rotating fermion systems, revealing how vortices interact with edge states and comparing behaviors to bosonic systems, with implications for quantum dots and traps.

Contribution

It demonstrates the coexistence and competition of vortices and edge-reconstructed states in larger fermion systems, extending understanding of quantum vortex phenomena.

Findings

Vortices form in small fermion systems under rotation.

Edge reconstruction influences vortex states, especially in larger systems.

Fermion vortices can be excited states, not just ground states.

Abstract

Vortices can form when finite quantal systems are set to rotate. In the limit of small particle numbers the vortex formation in a harmonically trapped fermion system, with repulsively interacting particles, shows similarities to the corresponding boson system, with vortices entering the rotating cloud for increasing rotation. We show that for a larger number of fermions, $N\gtrsim15$, the fermion vortices compete and co-exist with (Chamon-Wen) edge-reconstructed ground states, forcing some ground states, for instance the central single vortex, into the spectrum of excited states. Experimentally, the fermion system could for instance be a semiconductor heterostructure, a quantum dot, and the corresponding boson system a magneto optical trap (MOT).