Vortices in the Many-Body Excited States of Interacting Bosons in Two Dimension

TL;DR

This paper investigates how quantum vortices emerge in the eigenstates of interacting bosons in two dimensions, revealing both mean-field-like features and purely many-body quantum effects through ab initio and Bogoliubov analyses.

Contribution

It provides a detailed analysis of vortex formation in many-body eigenstates, bridging mean-field and quantum fluctuation perspectives in two-dimensional bosonic systems.

Findings

Vortices exhibit mean-field-like density and phase profiles.

Quantum fluctuations cause vortex smearing and center uncertainty.

Mean-field and many-body approaches are consistent in describing vortex features.

Abstract

Quantum vortices play an important role in the physics of two-dimensional quantum many-body systems, though they usually are understood in the single-particle framework like the mean-field approach. Inspired by the study on the relations between solitons and yrast states, we investigate here the emergence of vortices from the eigenstates of a N -body Hamiltonian of interacting particles trapped in a disk. We analyse states that appear by consecutively measuring the positions of particles. These states have densities, phases, and energies closely resembling mean-field vortices. We discuss similarities, but also point out purely many-body features, such as vortex smearing due to the quantum fluctuation of their center. The ab initio analysis of the many-body system, and mean-field approaches are supported by the analysis within the Bogoliubov approach.