Rotating Dirac fermions in a magnetic field in 1+2,3 dimensions

TL;DR

This paper investigates how external magnetic fields and rotation influence fermions in 1+2 and 1+3 dimensions, revealing effects like increased fermionic density, pion condensation, and potential superfluid phases relevant to heavy ion collisions.

Contribution

It introduces a novel mechanism linking rotation and magnetic fields to fermionic density increase and pion condensation, extending understanding of chiral effects in various dimensions.

Findings

Rotation causes fermionic density increase via Landau level sinking.

Strong interactions lead to pion condensation induced by centrifugation.

Potential formation of pion super-fluid phase in heavy ion collisions.

Abstract

We consider the effects of an external magnetic field on rotating fermions in 1+2,3 dimensions. The dual effect of a rotation parallel to the magnetic field causes a net increase in the fermionic density by centrifugation, which follows from the sinking of the particle lowest Landau level in the Dirac sea for free Dirac fermions. In 1+d = 2n dimensions, this effect is related to the chiral magnetic effect in 2n-2 dimensions. This phenomenon is discussed specifically for both weak and strong inter-fermion interactions in 1+2 dimensions. For QCD in 1+3 dimensions with Dirac quarks, we show that in the strongly coupled phase with spontaneously broken chiral symmetry, this mechanism reveals itself in the form of an induced pion condensation by centrifugation. We use this observation to show that this effect causes a shift in the chiral condensate in leading order, and to discuss the possibility for the formation of a novel pion super-fluid phase in present heavy ion collisions at collider energies.