Formation of a supergiant quantum vortex in a relativistic Bose-Einstein condensate driven by rotation and a parallel magnetic field

TL;DR

This paper investigates how interactions in a relativistic Bose-Einstein condensate under rotation and magnetic field lead to the formation of a supergiant quantum vortex, with implications for heavy ion collisions.

Contribution

It introduces a minimal model showing that interactions cause the condensate to form a supergiant vortex with system-sized circulation.

Findings

Ground state is a supergiant quantum vortex.

Vortex size is comparable to system size.

Excitation spectrum exhibits quadratic dispersion, indicating anisotropic Goldstone modes.

Abstract

Analysis based on the energy spectrum of noninteracting bosons shows that, under the circumstance of parallel rotation and magnetic field, charged bosons form a Bose-Einstein condensate because of the lift of the Landau level degeneracy by rotation [\textcolor{blue}{Y. Liu and I. Zahed, Phys. Rev. Lett. {\bf120}, 032001 (2018)}]. In this work, we study the interaction effect on the ground state of this Bose-Einstein condensate of charged bosons from the viewpoint of spontaneous symmetry breaking. We employ a minimal model for charged bosons with repulsive self-interaction. We find that the ground state of such a Bose-Einstein condensate is a supergiant quantum vortex, i.e., a quantized vortex with a large circulation. The size of the vortex is as large as the system size. The low-energy dispersion of the excitation spectra exhibits quadratic behavior, which is an anisotropic realization of the type-II Goldstone boson. Our study may give some implications to off-central relativistic heavy ion collisions, where large vorticity and magnetic fields can be generated.